Fix broken GitHub Actions CI workflow

[johnmcollier]

Our CI workflow had been failing for the past week or so, with the following error:

warning: Not a git repository. Use --no-index to compare two paths outside a working tree
usage: git diff --no-index [<options>] <path> <path>

Looking into it further, it seems related to what's described in actions/checkout#766, and adding git config --global --add safe.directory /github/workspace to the failing step seems to fix the issue

[amisevsk]

Another option here would be something like

    - name: Check CRD and schema generation
      run: |
        if [[ ! -z $(git status -s) ]]
        then
          echo 'Command `./docker-run.sh ./build.sh` did introduce changes, which should not be the case if it had been run as part of the PR. Please run it locally and check in the results as part of your PR.'
          git --no-pager diff
          exit 1
        fi

(this is how we handle it in DWO)

This could also be merged into the previous step:

    - name: Generate Go sources, CRDs and schemas
      run: |
        ./docker-run.sh ./build.sh
        if [[ ! -z $(git status -s) ]]
        then
          echo 'Command `./docker-run.sh ./build.sh` did introduce changes, which should not be the case if it had been run as part of the PR. Please run it locally and check in the results as part of your PR.'
          git --no-pager diff
          exit 1
        fi

[johnmcollier]

Thanks, that's a lot more elegant. Updated.

[openshift-ci]

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This pull-request has been approved by: amisevsk, johnmcollier

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[yangcao77]

/lgtm