Fix Collections import

Replace backport Collections class with stock JDK version

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/condition/CompositeRequestCondition.java

@@ -18,6 +18,7 @@ package org.springframework.web.servlet.mvc.condition;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 
 import javax.servlet.http.HttpServletRequest;
@@ -25,8 +26,6 @@ import javax.servlet.http.HttpServletRequest;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * Implements the {@link RequestCondition} contract by delegating to multiple
  * {@code RequestCondition} types and using a logical conjunction (' && ') to