Update snapshot publishing

Author: jamesfredley

.github/workflows/gradle.yml

@@ -75,6 +75,7 @@ jobs:
         uses: gradle/actions/setup-gradle@v4
       - name: "📤 Publish to Snapshot (repo.grails.org)"
         env:
+          GRAILS_PUBLISH_RELEASE: 'false'
           DEVELOCITY_ACCESS_KEY: ${{ secrets.DEVELOCITY_ACCESS_KEY }}
           MAVEN_PUBLISH_USERNAME: ${{ secrets.MAVEN_PUBLISH_USERNAME }}
           MAVEN_PUBLISH_PASSWORD: ${{ secrets.MAVEN_PUBLISH_PASSWORD }}