ci: Configure 4.x branch for snapshot publishing

- Add 4.x to push and PR workflow branch triggers
- Publish snapshots (not releases) when pushing to 4.x
- Disable push_to_repo for snapshot builds

Author: vpaturet

.github/workflows/pr.yml

@@ -3,6 +3,7 @@ on:
   pull_request:
     branches:
       - master
+      - 4.x
 jobs:
   maven-package:
     if: "!contains(github.event.head_commit.message, 'ci skip')"

.github/workflows/push.yml

@@ -3,6 +3,7 @@ on:
   push:
     branches:
       - master
+      - 4.x
 env:
     JFROG_USER: ${{ secrets.ARTIFACTORY_AUTH_USER }}
     JFROG_PASS: ${{ secrets.ARTIFACTORY_AUTH_TOKEN }}
@@ -64,5 +65,5 @@ jobs:
     uses: entur/gha-maven-central/.github/workflows/maven-publish.yml@v1
     secrets: inherit
     with:
-      push_to_repo: true
-      snapshot: false
+      push_to_repo: ${{ github.ref != 'refs/heads/4.x' }}
+      snapshot: ${{ github.ref == 'refs/heads/4.x' }}