Merge https://github.com/google/adk-python/pull/3932
## Summary
Upgrade GitHub Actions to their latest versions to ensure compatibility with Node 24, as Node 20 will reach end-of-life in April 2026.
## Changes
| Action | Old Version(s) | New Version | Release | Files |
|--------|---------------|-------------|---------|-------|
| `actions/checkout` | [`v5`](https://github.com/actions/checkout/releases/tag/v5) | [`v6`](https://github.com/actions/checkout/releases/tag/v6) | [Release](https://github.com/actions/checkout/releases/tag/v6) | analyze-releases-for-adk-docs-updates.yml, check-file-contents.yml, discussion_answering.yml, isort.yml, pr-triage.yml, pyink.yml, python-unit-tests.yml, stale-bot.yml, triage.yml, upload-adk-docs-to-vertex-ai-search.yml |
## Context
Per [GitHub's announcement](https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/), Node 20 is being deprecated and runners will begin using Node 24 by default starting March 4th, 2026.
### Why this matters
- **Node 20 EOL**: April 2026
- **Node 24 default**: March 4th, 2026
- **Action**: Update to latest action versions that support Node 24
### Security Note
Actions that were previously pinned to commit SHAs remain pinned to SHAs (updated to the latest release SHA) to maintain the security benefits of immutable references.
### Testing
These changes only affect CI/CD workflow configurations and should not impact application functionality. The workflows should be tested by running them on a branch before merging.
Co-authored-by: Xiang (Sean) Zhou <seanzhougoogle@google.com>
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/3932 from salmanmkc:upgrade-github-actions-node24 0ffbb0b7b5f63d27583f8c24781f2d3ca92c0c23
PiperOrigin-RevId: 845813166
Three fixes:
1. used "fetch-depth: 2" to ensure that files in all commits in the PR are checked
2. triggered by all changed ".py" files in the repo
3. merged the "check modified files" and "run Pyink" steps because $GITHUB_ENV cannot handle multi-line env vars without special treatment
PiperOrigin-RevId: 766793736
Liang WuandCopybara-Service
George WealeandCopybara-Service
Salman ChishtiandCopybara-Service
Giorgio BoaandCopybara-Service
Hangfei LinandCopybara-Service
Wei SunandCopybara-Service
Xiang (Sean) ZhouandCopybara-Service
