[actions] split doxygen/gh-pages (tag) from tests (push/PR).

.github/workflows/actions.yml

@@ -1,8 +1,8 @@
 name: build dist
 
 on:
-  create:
-    tags:
+  push:
+  pull_request:
 
 jobs:
   linux-build:
@@ -21,10 +21,3 @@ jobs:
         echo y | sudo apt-get install doxygen
     - name: run tests
       run: clang cmidi2_test.c -o cmidi2_test && ./cmidi2_test
-    - name: generate documentation
-      run: doxygen
-    - name: deploy to GitHub Pages
-      uses: JamesIves/[email protected]
-      with:
-        branch: gh-pages
-        folder: html

.github/workflows/actions_tags.yml

@@ -0,0 +1,28 @@
+name: build dist
+
+on:
+  create:
+    tags:
+
+jobs:
+  linux-build:
+    name: build on linux
+    runs-on: ubuntu-20.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v1
+      with:
+        submodules: recursive
+    - name: apt update
+      run: |
+        sudo apt-get update
+    - name: apt install
+      run: |
+        echo y | sudo apt-get install doxygen
+    - name: generate documentation
+      run: doxygen
+    - name: deploy to GitHub Pages
+      uses: JamesIves/[email protected]
+      with:
+        branch: gh-pages
+        folder: html