Remove accidental org.jetbrains:annotations usage.

See spring-projects/spring-data-build#2670

Author: mp911de

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/support/JpaRepositoryTests.java

@@ -24,7 +24,6 @@
 import java.util.Iterator;
 import java.util.List;
 
-import org.jetbrains.annotations.NotNull;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
@@ -151,7 +150,6 @@ void deleteAllByIdInBatchShouldConvertAnIterableToACollection() {
 private List<SampleEntityPK> ids = Arrays.asList(new SampleEntityPK("one", "eins"),
 new SampleEntityPK("three", "drei"));
 
-@NotNull
 @Override
 public Iterator<SampleEntityPK> iterator() {
 return ids.iterator();