chore: remove pull request trigger from Docker publish workflow

Author: lenoxys

.github/workflows/docker-publish.yml

@@ -4,8 +4,6 @@ on:
   push:
     branches: [ "main" ]
     tags: [ 'v*.*.*' ]
-  pull_request:
-    branches: [ "main" ]
 
 env:
   REGISTRY: ghcr.io