Fixes for cmd bot (#448)

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the issue_comment works from the refs/main branch by default, and
doesn't bring the PR context anyhow. Since i was testing it from the
default branch in paritytech-stg - it was working fine, but from real PR
non-default branch it didn't push result to PR branch.

---------

Co-authored-by: GitHub Action <[email protected]>

.github/workflows/cmd.yml

@@ -137,7 +137,13 @@ jobs:
               issue_number: context.issue.number,
               owner: context.repo.owner,
               repo: context.repo.repo,
-              body: `<details><summary>Command help:</summary>${{ steps.help.outputs.help }}</details>`
+              body: `<details><summary>Command help:</summary> 
+            
+            \`\`\`
+            ${{ steps.help.outputs.help }}
+            \`\`\` 
+            
+            </details>`
             })
 
       - name: Add confused reaction on failure
@@ -165,9 +171,49 @@ jobs:
               repo: context.repo.repo,
               content: '+1'
             })
+  
+  # Get PR branch name, because the issue_comment event does not contain the PR branch name
+  get-pr-branch:
+    needs: [clean, fellows]
+    runs-on: ubuntu-latest
+    outputs:
+      pr-branch: ${{ steps.get-pr.outputs.pr_branch }}
+      repo: ${{ steps.get-pr.outputs.repo }}
+    steps:
+      - name: Check if the issue is a PR
+        id: check-pr
+        run: |
+          if [ -n "${{ github.event.issue.pull_request.url }}" ]; then
+            echo "This is a pull request comment"
+          else
+            echo "This is not a pull request comment"
+            exit 1
+          fi
+
+      - name: Get PR Branch Name and Repo
+        if: steps.check-pr.outcome == 'success'
+        id: get-pr
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const pr = await github.rest.pulls.get({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              pull_number: context.issue.number,
+            });
+            const prBranch = pr.data.head.ref;
+            const repo = pr.data.head.repo.full_name;
+            return { pr_branch: prBranch, repo: repo };
+          result-encoding: string
+
+      - name: Use PR Branch Name and Repo
+        run: |
+          echo "The PR branch is ${{ steps.get-pr.outputs.pr_branch }}"
+          echo "The repository is ${{ steps.get-pr.outputs.repo }}"
+
 
   cmd:
-    needs: [clean, fellows]
+    needs: [get-pr-branch, fellows]
     env:
       JOB_NAME: 'cmd'
     if: ${{ startsWith(github.event.comment.body, '/cmd') && !contains(github.event.comment.body, '--help') && contains(needs.fellows.outputs.github-handles, github.event.sender.login) }}
@@ -225,7 +271,8 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.head_ref }}
+          repository: ${{ needs.get-pr-branch.outputs.repo }}
+          ref: ${{ needs.get-pr-branch.outputs.pr-branch }}
 
       - name: Set rust version via common env file
         run: cat .github/env >> $GITHUB_ENV
@@ -256,7 +303,8 @@ jobs:
         env:
           CMD: ${{ steps.get-pr-comment.outputs.group2 }} # to avoid "" around the command
         run: |
-          echo "Running command: $CMD"
+          echo "github.ref: ${{ github.ref }}"
+          echo "Running command: $CMD on branch ${{ needs.get-pr-branch.outputs.pr-branch }}"
           git remote -v
           python3 .github/scripts/cmd/cmd.py $CMD
           git status
@@ -268,11 +316,11 @@ jobs:
             git config --local user.email "[email protected]"
             git config --local user.name "GitHub Action"
             
-            git pull origin ${{ github.head_ref }}
+            git pull origin ${{ needs.get-pr-branch.outputs.pr-branch }}
             git add .
             git restore --staged Cargo.lock # ignore changes in Cargo.lock
             git commit -m "Update from ${{ github.actor }} running command '${{ steps.get-pr-comment.outputs.group2 }}'" || true
-            git push origin ${{ github.head_ref }}
+            git push origin ${{ needs.get-pr-branch.outputs.pr-branch }}
           else
             echo "Nothing to commit";
           fi
@@ -290,7 +338,7 @@ jobs:
             --no-color \
             --change added changed \
             --ignore-errors \
-            refs/remotes/origin/main ${{ github.ref }})
+            refs/remotes/origin/main refs/heads/${{ needs.get-pr-branch.outputs.pr-branch }})
           
           # Save the multiline result to the output
           {