Dynamically populate repositories used in Ant/Maven integration tests

Update build scripts and tests so that repository settings are copied
dynamically from the build.

See gh-42333

spring-boot-project/spring-boot-tools/spring-boot-antlib/src/it/sample/ivysettings.xml

@@ -8,8 +8,8 @@
 				<ivy pattern="${user.home}/.m2/[organisation]/[module]/[revision]/[module]-[revision].pom" />
 			</filesystem>
 			<ibiblio name="ibiblio" m2compatible="true" />
-			<ibiblio name="spring-milestones" m2compatible="true" root="https://repo.spring.io/milestone" />
-			<ibiblio name="spring-snapshots" m2compatible="true" root="https://repo.spring.io/snapshot" />
+			<!-- {spring.mavenRepositories} -->
 		</chain>
 	</resolvers>
 </ivysettings>
+