Update release-on-maven-central.yml

Added trigger to publish on published event as the tag event is not being triggered when publishing a release anymore

Author: shannah

.github/workflows/release-on-maven-central.yml

@@ -5,6 +5,8 @@ name: Release on Maven Central
 on:
   push:
     tags: '*'
+  release:
+    types: [published]
 jobs:
   build:
     runs-on: ubuntu-latest