Use libs-snapshot repository for milestone visibility.

See #2068

Author: mp911de

pom.xml

@@ -141,7 +141,7 @@
 	<repositories>
 		<repository>
 			<id>spring-libs-snapshot</id>
-			<url>https://repo.spring.io/snapshot</url>
+			<url>https://repo.spring.io/libs-snapshot</url>
 		</repository>
 	</repositories>