Update GitHub Actions workflows to use 'master' branch

.github/workflows/docker.yml

@@ -2,7 +2,7 @@ name: Build and Publish Docker Image
 
 on:
   push:
-    branches: [ main ]
+    branches: [ master ]
     tags: [ 'v*' ]
 
 env:
@@ -47,7 +47,7 @@ jobs:
         uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83  # v6.18.0
         with:
           context: .
-          file: Dockerfile
+          file: docker/Dockerfile
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}

.github/workflows/safety.yml

@@ -1,7 +1,7 @@
 name: Safety
 on:
   push:
-    branches: [ main ]
+    branches: [ master ]
   schedule:
     - cron: '0 0 * * 0' # weekly
 jobs:

.github/workflows/test.yml

@@ -1,12 +1,10 @@
-# TODO: Update to use specific commit hashes for the actions for better supply chain security.
-
 name: Run Tests
 
 on:
   push:
-    branches: [ main ]
+    branches: [ master ]
   pull_request:
-    branches: [ main ]
+    branches: [ master ]
 
 jobs:
   test: