Upgrade to Groovy 2.5.13

Closes gh-22526

Author: snicoll

spring-boot-project/spring-boot-dependencies/build.gradle

@@ -362,10 +362,7 @@ bom {
 			]
 		}
 	}
-	library("Groovy", "2.5.12") {
-		prohibit("[2.5.13,2.5.14)") {
-			because "regression with @Log"
-		}
+	library("Groovy", "2.5.13") {
 		group("org.codehaus.groovy") {
 			imports = [
 				"groovy-bom"