test(@angular/build): remove isViteRun from dev-server test harness #3126

Job	Run time
list	23s
workflow (modules-builder-tests)	2m 3s
workflow (devkit-core-tests)	1m 39s
workflow (build-cli)	1m 46s
workflow (devkit-core-tests-rerun)	1m 38s
workflow (build-unit-tests)	2m 35s
	10m 4s

Provide feedback