Make sure a label is added to each PR

.github/workflows/ensure_label.yml

@@ -0,0 +1,20 @@
+name: PR should have a language label
+on:
+  pull_request:
+    types: [opened, labeled, unlabeled, synchronize]
+
+jobs:
+  label:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - uses: mheap/github-action-required-labels@v5
+        with:
+          mode: minimum
+          count: 1
+          add_comment: true
+          use_regex: true
+          labels: ".*"
+          message: "Please add a label with the relevant language(s) to be able to merge this PR"