Rename default branch to main (#61)

Author: drehelis

.github/workflows/build-push.yml

@@ -2,7 +2,7 @@ name: build-push
 
 on:
   push:
-    branches: ['master']
+    branches: ['main']
     paths:
       - .github/workflows/build-push.yml
       - Dockerfile

.github/workflows/pytest.yml

@@ -2,9 +2,9 @@ name: pytest
 
 on:
   push:
-    branches: [ "master" ]
+    branches: [ "main" ]
   pull_request:
-    branches: [ "master" ]
+    branches: [ "main" ]
 
 permissions:
   contents: read