ci: add vale style check

Signed-off-by: David Karlsson <35727626+dvdksn@users.noreply.github.com>

.github/workflows/build.yml

@@ -35,6 +35,14 @@ jobs:
             *.cache-from=type=gha,scope=build
             *.cache-to=type=gha,scope=build,mode=max
 
+  vale:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+      - uses: errata-ai/vale-action@38bf078c328061f59879b347ca344a718a736018 # v2.1.0
+        with:
+          files: content
+
   validate:
     runs-on: ubuntu-22.04
     strategy: