Check typos from CI

Signed-off-by: Martin Pool <mbp@sourcefrog.net>

.github/workflows/typos.yml

@@ -0,0 +1,13 @@
+name: Typos
+on: [pull_request]
+
+jobs:
+  run:
+    name: Spell check with Typos
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Check spelling
+        uses: crate-ci/typos@master