Switch s-b-server-tests from libs-snapshot to snapshot and milestone

Closes gh-27233

Author: wilkinsona

spring-boot-tests/spring-boot-integration-tests/spring-boot-server-tests/src/test/resources/pom-template.xml

@@ -55,19 +55,33 @@
 	<repositories>
 		<repository>
 			<id>spring-snapshots</id>
-			<url>https://repo.spring.io/libs-snapshot</url>
+			<url>https://repo.spring.io/snapshot</url>
 			<snapshots>
 				<enabled>true</enabled>
 			</snapshots>
 		</repository>
+		<repository>
+			<id>spring-milestones</id>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</repository>
 	</repositories>
 	<pluginRepositories>
 		<pluginRepository>
 			<id>spring-snapshots</id>
-			<url>https://repo.spring.io/libs-snapshot</url>
+			<url>https://repo.spring.io/snapshot</url>
 			<snapshots>
 				<enabled>true</enabled>
 			</snapshots>
 		</pluginRepository>
+		<pluginRepository>
+			<id>spring-milestones</id>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</pluginRepository>
 	</pluginRepositories>
 </project>