chore: lock activemq-broker major version

Author: slandelle

.scala-steward.conf

@@ -1 +1,7 @@
 commits.message = "chore: update ${artifactName} from ${currentVersion} to ${nextVersion}"
+
+updates.pin = [
+  // major API changes
+  // activemq 6 uses JakartaEE
+  { groupId = "org.apache.activemq", artifactId="activemq-broker", version="5." }
+]