fix(ci): move github workflow to correct location

I used Github's UI to create this from the template (which I _never_ do,
instead opting for the CLI) and some how this ended up in the project
root, instead of in the .github/workflows directory. 🤷

Back to the command line for me...

.github/workflows/pr-automerge-open-release.yml

@@ -0,0 +1,67 @@
+# For non-draft changes to Named Release branches:
+# - Check if the user belongs to a maintainers team.
+# - If so, approve the pull request.
+#   - Tag community-engineering (for now) and the maintainers team.
+#   - Merge the PR when the author comments `@edx-community-bot merge`.
+# Required organization secrets
+# - CC_GITHUB_TOKEN=...
+# - CC_TEAM_CHAMPIONS=org/team-name
+# - CC_TEAM_CONTRIBUTORS_ORG=org
+# - CC_TEAM_CONTRIBUTORS_TEAM=team-name
+---
+name: automerge BTR open-release PRs
+on:
+  issue_comment:
+    branches:
+    - open-release/*
+    types:
+    - created
+    - edited
+  pull_request_target:
+    branches:
+    - open-release/*
+    types:
+    - opened
+    - edited
+    - ready_for_review
+jobs:
+  automerge:
+    if: ${{ (github.event.issue.pull_request && !github.event.issue.pull_request.draft) || (github.event.pull_request && !github.event.pull_request.draft) }}
+    runs-on: ubuntu-latest
+    steps:
+    - name: lookup teams
+      id: teams
+      uses: tspascoal/get-user-teams-membership@v1
+      with:
+        username: "${{ github.actor }}"
+        organization: ${{ secrets.CC_TEAM_CONTRIBUTORS_ORG }}
+        team: ${{ secrets.CC_TEAM_CONTRIBUTORS_TEAM }}
+        GITHUB_TOKEN: "${{ secrets.CC_GITHUB_TOKEN || secrets.GITHUB_TOKEN }}"
+    - name: approve PR
+      if: ${{ steps.teams.outputs.isTeamMember == 'true' && (github.event.action == 'opened' || github.event.action == 'ready_for_review') }}
+      uses: andrewmusgrave/automatic-pull-request-review@0.0.5
+      with:
+        repo-token: ${{ secrets.CC_GITHUB_TOKEN || secrets.GITHUB_TOKEN }}
+        event: APPROVE
+        body: |
+          :+1:
+
+          When you're ready to merge, add a comment that says
+          > @edx-community-bot merge
+
+          and we'll handle the rest!
+          CC: @${{ secrets.CC_TEAM_CHAMPIONS }} @${{ secrets.CC_TEAM_CONTRIBUTORS_ORG }}/${{ secrets.CC_TEAM_CONTRIBUTORS_TEAM }}
+    - name: label PR as auto-mergeable
+      if: ${{ steps.teams.outputs.isTeamMember == 'true' && contains(github.event.comment.body, '@edx-community-bot merge') }}
+      uses: andymckay/labeler@978f846c4ca6299fd136f465b42c5e87aca28cac
+      with:
+        add-labels: 'automerge'
+        repo-token: ${{ secrets.CC_GITHUB_TOKEN || secrets.GITHUB_TOKEN }}
+    - name: automerge
+      uses: "pascalgn/automerge-action@v0.13.1"
+      env:
+        GITHUB_TOKEN: "${{ secrets.CC_GITHUB_TOKEN || secrets.GITHUB_TOKEN }}"
+        MERGE_COMMIT_MESSAGE: |
+          merge(#{pullRequest.number}): {pullRequest.title}
+
+          {pullRequest.body}