Update .github/release/check_maven_central.py

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: suztomo

.github/release/check_maven_central.py

@@ -116,6 +116,8 @@ def main():
         print("\nSummary of published versions found in local pom.xml files:")
         for item in sorted(found_published):
             print(item)
+        import sys
+        sys.exit(1)
     else:
         print("\nNo published non-SNAPSHOT versions found.")