chore: split build and doc diff checker workflows (#323)

* chore: split build and doc diff checker workflos

* chore: rename

.github/workflows/build.yml

@@ -1,4 +1,4 @@
-name: Build
+name: Build and Scan
 on:
   push:
     branches:
@@ -14,17 +14,6 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Run make docs
-        run: make docs
-
-      - name: Check for differences
-        run: |
-          if ! git diff --quiet; then
-            echo "There are differences in the generated documentation."
-            git diff
-            exit 1
-          fi
-
       - name: Set up Go
         uses: actions/setup-go@v3
         with:

.github/workflows/docs.yml

@@ -0,0 +1,26 @@
+name: Docs
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types: [ opened, synchronize, reopened ]
+jobs:
+  check_diff:
+    name: Check Generated Docs Diff
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - name: Run make docs
+        run: make docs
+
+      - name: Check for differences
+        run: |
+          if ! git diff --quiet; then
+            echo "There are differences in the generated documentation. Run `make docs` to fix."
+            git diff
+            exit 1
+          fi