Include `GITHUB_TOKEN`/`GITEA_TOKEN` secrets for actions triggered by
pull requests
This makes it consistent with the environment variables which you can
already access
```shell
echo env: $GITHUB_TOKEN
echo expression: ${{ secrets.GITHUB_TOKEN }}
```
before

after

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Co-authored-by: Jason Song <[email protected]>
Co-authored-by: Giteabot <[email protected]>