Remove processed annotations plugin declaration

See gh-41981

Author: wilkinsona

buildSrc/build.gradle

@@ -116,10 +116,6 @@ gradlePlugin {
 id = "org.springframework.boot.optional-dependencies"
 implementationClass = "org.springframework.boot.build.optional.OptionalDependenciesPlugin"
 }
-processedAnnotationsPlugin {
-id = "org.springframework.boot.processed-annotations"
-implementationClass = "org.springframework.boot.build.processors.ProcessedAnnotationsPlugin"
-}
 starterPlugin {
 id = "org.springframework.boot.starter"
 implementationClass = "org.springframework.boot.build.starters.StarterPlugin"