Transform Maven settings with proper plugin repository tag

This commit adapts d44e7c9 to transforms plugin repositories using the
correct root tag. Previously, they were transformed with the regular
<repository> tag, which is invalid.

Closes gh-42687

spring-boot-project/spring-boot-tools/spring-boot-antlib/build.gradle

@@ -28,7 +28,7 @@ dependencies {
 task syncIntegrationTestSources(type: Sync) {
 	destinationDir file("${buildDir}/it")
 	from file("src/it")
-	filter(springRepoistoryTransformers.ant())
+	filter(springRepositoryTransformers.ant())
 }
 
 processResources {