CI: Fix certain GitHub CI variables

[riley-dixon]

AIHIPFILE-160

[Copilot]

Pull request overview

This PR updates GitHub Actions workflows to rely on the runner-provided GITHUB_* environment variables (e.g., GITHUB_REF, GITHUB_JOB, GITHUB_RUN_ID) instead of ${{ github.* }} expressions in several shell steps, primarily for deriving PR numbers, container names, and CI tags.

Changes:

• Replace ${{ github.ref }} with ${GITHUB_REF} when computing AIS_PR_NUMBER / tags.
• Replace ${{ github.job }} / ${{ github.run_id }} / ${{ github.base_ref }} / ${{ github.head_ref }} with GITHUB_* env vars in relevant run steps.
• Keep existing workflow behavior while standardizing variable sourcing across workflows.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
.github/workflows/test-ais-system.yml	Use GITHUB_REF to derive AIS_PR_NUMBER for AIS system/FIO test jobs.
.github/workflows/hipfile-nvidia.yml.disabled	Use GITHUB_REF to derive PR number and image tag (workflow currently disabled).
.github/workflows/build-ais.yml	Use GITHUB_REF, GITHUB_RUN_ID, and GITHUB_JOB for PR/container naming in the build workflow.
.github/workflows/build-ais-nvidia.yml	Use GITHUB_REF and GITHUB_JOB for PR/container naming in Nvidia build workflow.
.github/workflows/build-ais-ci-image.yml	Use GITHUB_REF / GITHUB_HEAD_REF for CI image tag/label metadata.
.github/workflows/ais-ci.yml	Use GITHUB_BASE_REF when fetching base ref and computing CI flags.

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[Copilot]

Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

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