Only push images when not triggered via a PR

Author: chadlwilson

.github/workflows/docker-publish.yml

@@ -4,6 +4,9 @@ on:
   create:
     tags:
       - 'v*'
+  pull_request:
+    branches:
+      - master
 
 env:
   REGISTRY_IMAGE: gocddev/gocd-dev-build
@@ -76,6 +79,7 @@ jobs:
           retention-days: 1
 
   linux-push:
+    if: ${{ github.event_name != 'pull_request' }}
     name: linux-push-${{ matrix.distro }}
     runs-on: ubuntu-latest
     needs:
@@ -160,3 +164,4 @@ jobs:
           registry: docker.io
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
+          pushImage: ${{ github.event_name != 'pull_request' }}