Fix Android Release workflow: replace expired GH_TOKEN with built-in github.token

[Copilot]

The Android Release CI job was failing with HttpError: Bad credentials because secrets.GH_TOKEN (a custom PAT) had expired or been revoked.

Changes

• .github/workflows/android-release.yml: Replace ${{ secrets.GH_TOKEN }} with ${{ github.token }} in all four steps that use it:
  • cardinalby/git-get-release-action (read release by tag)
  • Three svenstaro/upload-release-action steps (upload APK, icon, manifest)

# Before
env:
  GITHUB_TOKEN: ${{ secrets.GH_TOKEN }}

# After
env:
  GITHUB_TOKEN: ${{ github.token }}

The built-in github.token is auto-provisioned per run with sufficient permissions to read and write releases on the same repository, eliminating the dependency on a manually managed PAT.