bump nightly test to 26.06

[rgsl888prabhu]

Description

Bumpy nightly tests for 26.06 and disable 26.04

Checklist

• I am familiar with the Contributing Guidelines.
• Testing
  • New or existing tests cover these changes
  • Added tests
  • Created an issue to follow-up
  • NA
• Documentation
  • The documentation is up to date with these changes
  • Added new documentation
  • NA

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 7fd2ab13-feed-43b9-a5dc-18b019745704

📥 Commits

Reviewing files that changed from the base of the PR and between 24fdb60 and a0a0b40.

📒 Files selected for processing (1)

• .github/workflows/nightly.yaml

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📝 Walkthrough

Walkthrough

Updated GitHub Actions workflow job matrix to replace the cuopt_branch matrix entry from release/26.04 to release/26.06, changing which release branch is referenced when the nightly workflow dispatches build.yaml via the CUOPT_BRANCH parameter.

Changes

Cohort / File(s)	Summary
GitHub Actions Workflow Configuration .github/workflows/nightly.yaml	Updated cuopt_branch matrix entry from release/26.04 to release/26.06

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically describes the main change: updating nightly tests to use version 26.06.
Description check	✅ Passed	The description is related to the changeset, indicating the intent to update nightly CI to use 26.06 and disable 26.04, which aligns with the workflow file changes.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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