Suppress varargs warning

Prior to this commit, the Gradle build failed due to a varargs warning.

See gh-25311

spring-web/src/main/java/org/springframework/http/converter/json/Jackson2ObjectMapperBuilder.java

@@ -596,6 +596,7 @@ public class Jackson2ObjectMapperBuilder {
 	 * @see com.fasterxml.jackson.databind.Module
 	 */
 	@SafeVarargs
+	@SuppressWarnings("varargs")
 	public final Jackson2ObjectMapperBuilder modulesToInstall(Class<? extends Module>... modules) {
 		this.moduleClasses = modules;
 		this.findWellKnownModules = true;