feat: spellcheck Actions workflow

GitHub Actions workflow for the CSpell spellcheck. Action from
https://github.com/streetsidesoftware/cspell-action

Additional dictionary has to be installed seperately upfront, as described in
streetsidesoftware/cspell-action#181

Signed-off-by: Nico Rikken <nico.rikken@alliander.com>

.github/workflows/spellcheck.yml

@@ -0,0 +1,13 @@
+name: 'Check spelling'
+on: # rebuild any PRs and main branch changes
+  pull_request:
+  push:
+
+jobs:
+  spellcheck: # run the action
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Install dictionaries
+        run: npm install @cspell/dict-nl-nl
+      - uses: streetsidesoftware/cspell-action@v2

cspell.config.yaml

@@ -6,3 +6,5 @@ ignorePaths:
   # Ignore License files that should not be touched
   - "LICENSE"
   - "LICENSES/*"
+import:
+  - "@cspell/dict-nl-nl/cspell-ext.json"