Update default branch ref

.github/workflows/docker.yml

@@ -4,12 +4,12 @@ on:
   workflow_dispatch:
   push:
     branches:
-      - master
+      - prime
     tags:
       - "*"
   pull_request:
     branches:
-      - master
+      - prime
 
 jobs:
   # Outputs from this job aren't really used, but it's here to verify that the Dockerfile builds correctly
@@ -44,8 +44,8 @@ jobs:
           if-no-files-found: error
 
   deploy:
-    # Deploy to DockerHub only on tag push or master branch push
-    if: ${{ github.ref_type == 'tag' || github.ref_type == 'branch' && github.ref_name == 'master' }}
+    # Deploy to DockerHub only on tag push or prime branch push
+    if: ${{ github.ref_type == 'tag' || github.ref_type == 'branch' && github.ref_name == 'prime' }}
 
     runs-on: ubuntu-latest
     timeout-minutes: 10