chore: pin GitHub Actions to specific commit hashes

[capytan]

Motivation / Background

This Pull Request has been created to improve the security and stability of our GitHub Actions workflow by pinning action versions to specific commit hashes. This follows the security best practice recommended by GitHub to prevent potential supply chain attacks.

Detail

This Pull Request changes the version references in our GitHub Actions workflow from floating version tags to specific commit hashes:

• Updates actions/checkout from v4 to v4.2.2 (commit hash: 11bd71901bbe5b1630ceea73d27597364c9af683)
• Updates actions/setup-java from v3 to v3.13.0 (commit hash: 0ab4596768b603586c0de567f2430c30f5b0d2b0)
• Updates actions/cache from v2 to commit hash 8492260343ad570701412c2f464a5877dc76bace of the same version
• Updates ruby/setup-ruby from v1 to v1.227.0 (commit hash: 1a615958ad9d422dd932dc1d5823942ee002799f)

Benefits of this change:

• Improves reproducibility of workflow runs
• Prevents unexpected action updates
• Provides clear identification of action versions in use

Checklist

• This PR contains changes related to a single purpose (pinning action versions)
• Commit message includes detailed description of changes and rationale
• No tests needed as this is a workflow configuration change
• No CHANGELOG update needed as this is an internal workflow change

[JASON13F]

対応ありがとうございます！LGTM！

[GOTO-TSL]

ありがとうございます！