stage-vote-release: avoid failures when "init" does not exist

Author: vlsi

plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/StageVoteReleasePlugin.kt

@@ -145,7 +145,9 @@ class StageVoteReleasePlugin @Inject constructor(private val instantiator: Insta
 
         configureNexusStaging(releaseExt)
 
-        tasks.named("init").hide()
+        plugins.withId("build-init") {
+            tasks.named("init").hide()
+        }
         hideMavenPublishTasks()
 
         // Tasks from NexusStagingPlugin