fix(ci): use shell: bash for molecule test step

The inline molecule runner uses bashisms (here-strings `<<<`,
parameter expansion) that dash/sh doesn't support. Gitea Actions
defaults to sh, causing "Syntax error: redirection unexpected".

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.gitea/workflows/ci.yml

@@ -200,6 +200,7 @@ jobs:
           fi
       - name: Run molecule tests
         if: env.SKIP != 'true' && steps.prune.outputs.should-run != 'false'
+        shell: bash
         env:
           CI_GITEA_API_TOKEN: ${{ secrets.CI_GITEA_API_TOKEN }}
           CI_GITEA_USERNAME: ${{ vars.CI_GITEA_USERNAME }}