fix(ci): use correct default branch name

The `on: push` workflow rule worked against master, our default branch
is main. Correct that so our pipelines actually run in MR.

Signed-off-by: Christoph Steiger <[email protected]>

Author: Urist-McGit

.github/workflows/lint.yml

@@ -7,7 +7,7 @@ name: Lint Python Code
 on:
   pull_request:
     branches:
-      - master
+      - main
   push:
 
 jobs:

.github/workflows/test.yml

@@ -7,7 +7,7 @@ name: Run Tests
 on:
   pull_request:
     branches:
-      - master
+      - main
   push:
 
 jobs: