Fix compilation error in ResolvableTypeTests

Author: sbrannen

spring-core/src/test/java/org/springframework/core/ResolvableTypeTests.java

@@ -41,6 +41,7 @@
 import java.util.SortedSet;
 import java.util.TreeSet;
 import java.util.concurrent.Callable;
+import java.util.function.Consumer;
 
 import org.assertj.core.api.AbstractAssert;
 import org.junit.jupiter.api.Test;