Update build.yml

Configure GH Actions on develop and master branches... the install_and_actions branch should be deleted eventually.

.github/workflows/build.yml

@@ -5,9 +5,9 @@ name: Build & test on different versions
 
 on:
   push:
-    branches: [ install_and_actions ]
-#  pull_request:
-#    branches: [ install_and_actions ]
+    branches: [ master, develop ]
+  pull_request:
+    branches: [ master, develop ]
 
 jobs:
   build:
@@ -101,4 +101,4 @@ jobs:
         pip install .
     - name: Test with pytest
       run: |
-        pytest -v
+        pytest -v