Refactor copilot action usage in copilot-comment.yml and add test-copilot.yml workflow

Author: austenstone

.github/workflows/copilot-comment.yml

@@ -5,7 +5,7 @@ jobs:
     if: ${{ startsWith(github.event.comment.body, '/copilot') }}
     runs-on: ubuntu-latest
     steps:
-      - uses: austenstone/copilot-cli-actions/.github/actions/copilot-command@main
+      - uses: austenstone/copilot-cli-actions/.github/actions/copilot@main
         with:
           github-token: ${{ secrets.PAT }}
           prompt: |

.github/workflows/test-copilot.yml

@@ -0,0 +1,12 @@
+on: push
+
+jobs:
+  copilot:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: austenstone/copilot-cli-actions/.github/actions/copilot@main
+        with:
+          github-token: ${{ secrets.PAT }}
+          prompt: |
+            Create annotations and write a job summary using mcp tools.
+