Added workflow to check invalid labels

Author: romancardenas

riscv-rt/.github/workflows/changelog.yaml

@@ -6,7 +6,7 @@ on:
     types: [opened, synchronize, reopened, ready_for_review, labeled, unlabeled]
 
 jobs:
-  check_changelog:
+  changelog-check:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code

riscv-rt/.github/workflows/gh_labels.yaml

@@ -0,0 +1,19 @@
+name: Check Labels
+on:
+  merge_group:
+  pull_request:
+    types: [opened, synchronize, reopened, ready_for_review, labeled, unlabeled]
+
+jobs:
+  label:
+    runs-on: ubuntu-latest
+    steps:
+      - id: labels-check
+        uses: mheap/github-action-required-labels@v5
+        with:
+          mode: exactly
+          count: 0
+          labels: "work in progress, do not merge"
+          add_comment: true
+          message: "This PR is being prevented from merging because it presents one of the blocking labels: {{ provided }}."
+

riscv-rt/CHANGELOG.md

@@ -9,7 +9,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
-- New GitHub worklow for checking modifications on CHANGELOG.md
+- New GitHub workflow for checking invalid labels in PRs
+- New GitHub workflow for checking modifications on CHANGELOG.md
 - New GitHub workflow for checking clippy lints in PRs
 
 ### Changed