Fix botched merge of spring-boot-maven-plugin's build.gradle

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/build.gradle

@@ -141,6 +141,46 @@ tasks.named("documentPluginGoals") {
 	]
 }
 
+def antoraMavenPluginLocalAggregateContent  = tasks.register("antoraMavenPluginLocalAggregateContent", Zip) {
+	destinationDirectory = layout.buildDirectory.dir('generated/docs/antora-content')
+	archiveClassifier = "maven-plugin-local-aggregate-content"
+	from(tasks.getByName("generateAntoraYml")) {
+		into "modules"
+	}
+}
+
+def antoraMavenPluginAggregateContent = tasks.register("antoraMavenPluginAggregateContent", Zip) {
+	destinationDirectory = layout.buildDirectory.dir('generated/docs/antora-content')
+	archiveClassifier = "maven-plugin-aggregate-content"
+	from(documentPluginGoals) {
+		into "modules/maven-plugin/partials/goals"
+	}
+}
+
+def antoraMavenPluginCatalogContent = tasks.register("antoraMavenPluginCatalogContent", Zip) {
+	destinationDirectory = layout.buildDirectory.dir('generated/docs/antora-content')
+	archiveClassifier = "maven-plugin-catalog-content"
+	from(javadoc) {
+		into "api/java"
+	}
+}
+
+tasks.named("generateAntoraPlaybook") {
+	xrefStubs = ["appendix:.*", "api:.*", "reference:.*", "how-to:.*"]
+	alwaysInclude = [name: "maven-plugin", classifier: "local-aggregate-content"]
+	dependsOn antoraMavenPluginLocalAggregateContent
+}
+
+
+tasks.named("antora") {
+	inputs.files(antoraMavenPluginLocalAggregateContent, antoraMavenPluginAggregateContent, antoraMavenPluginCatalogContent)
+}
+
+artifacts {
+	antoraContent antoraMavenPluginAggregateContent
+	antoraContent antoraMavenPluginCatalogContent
+}
+
 tasks.named("dockerTest").configure {
 	dependsOn tasks.named("prepareMavenBinaries")
 }