Run GitHub workflows on default branch as well

Author: vlaci

.github/workflows/pythonpackage.yml

@@ -9,6 +9,9 @@ on:
       - '**.css'
       - '**.lock'
       - 'Makefile'
+  push:
+    branches:
+      - 'main'
 
 jobs:
   build:

README.md

@@ -2,6 +2,9 @@
 
 Development tools for Textual.
 
+![checks](https://github.com/Textualize/textual-dev/actions/workflows/pythonpackage.yml/badge.svg?event=push)
+
+
 This package contains the `textual` command line app, which will help to develop Textual applications.
 
 See [Getting Started](https://textual.textualize.io/getting_started/) for how to use it.