ITSMFT: fix clusterizer merge correctly connected pixels

[f3sch]

I just want to check the CI, patch comes from https://its.cern.ch/jira/browse/O2-6424.

[github-actions]

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[alibuild]

Error while checking build/O2/fullCI_slc9 for 18ea114 at 2025-12-10 18:57:

## sw/BUILD/O2-sim-challenge-test-latest/log
./sim-challenge.log[ERROR] Workflow crashed - PID 11744 (HMP-Clusterization) did not exit correctly however it's not clear why. Exit code forced to 128.
./sim-challenge.log[ERROR]  - Device HMP-Clusterization: pid 11744 (exit 128)
./sim-challenge.log[ERROR] SEVERE: Device HMP-Clusterization (11744) returned with 128
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/37}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/38}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/40}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/42}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/43}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/45}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/46}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/47}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/48}
./digi.log[ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/49}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/37}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/38}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/40}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/42}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/43}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/45}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/46}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/47}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/48}
./digi.log[4677:TRDDigitizer]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/49}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/37}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/38}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/40}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/42}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/43}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/45}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/46}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/47}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/48}
./digi.log[4764:TPCDigitizer_1]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/49}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/37}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/38}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/40}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/42}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/43}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/45}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/46}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/47}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/48}
./digi.log[4619:SimReader]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/49}
./digi.log[4880:TPCDigitizer_10]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/37}
./digi.log[4880:TPCDigitizer_10]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/38}
./digi.log[4880:TPCDigitizer_10]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/40}
./digi.log[4880:TPCDigitizer_10]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/42}
./digi.log[4880:TPCDigitizer_10]: [ERROR] Found duplicate input binding with different spec.:collisioncontext {SIM/COLLISIONCONTEXT/43}
[0 more errors; see full log]

Full log here.