Add git commit message linting

As implemented and configured in other Submariner repos.

Signed-off-by: Daniel Farrell <dfarrell@redhat.com>

.github/workflows/linting.yml

@@ -19,6 +19,17 @@ jobs:
         with:
           commits: ${{ steps.get-pr-commits.outputs.commits }}
 
+  gitlint:
+    name: Commit Message(s)
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out the repository
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - name: Run gitlint
+        run: make gitlint
+
   markdown-link-check:
     name: Markdown Links (modified files)
     runs-on: ubuntu-latest