make the environment conditional

Author: pschichtel

.github/workflows/gradle.yml

@@ -10,7 +10,7 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
-    environment: sonatype-central
+    environment: ${{ (github.ref == 'refs/heads/master' || startsWith(github.ref, 'refs/tags/javacan-') ) && 'sonatype-central' || null }}
     steps:
       - uses: actions/checkout@v4
         with: