Add checks workflow

.github/workflows/checks.yml

@@ -0,0 +1,24 @@
+name: Pull request checks
+
+on:
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  check_nanorc_files:
+    name: Check nanorc files
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout branch
+        uses: actions/checkout@v3
+
+      - name: Run nano
+        run: |
+          echo "include \"$(pwd)/*.nanorc\"" > ~/.nanorc
+          echo "test" | nano 2> log.txt || grep "^Error" log.txt && exit 1 || exit 0
+
+#       - name: Parse nanorc files
+#         run: |
+#           # see https://www.nano-editor.org/dist/latest/nano.html#Nanorc-Files
+#           grep -v -E "^(#|syntax|header|magic|formatter|linter|comment|tabgives|color|icolor|include|extendsyntax|$)" *.nanorc && exit 1 || exit 0