set up spellcheck

Signed-off-by: szaimen <szaimen@e.mail.de>

.github/workflows/spellcheck.yml

@@ -0,0 +1,18 @@
+name: 'Spellcheck'
+
+on:
+  pull_request:
+  push:
+
+jobs:
+  spellcheck:
+    name: Check spelling
+    runs-on: ubuntu-latest
+    steps:
+      - name: spelling or typos
+        uses: actions/checkout@v2
+      - name: misspell
+        uses: reviewdog/action-misspell@v1
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          locale: "US"