Review checkstyle rule to prevent non BDD mockito imports

Closes gh-20902

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/hazelcast/Hazelcast4HazelcastHealthIndicatorTests.java

@@ -31,7 +31,7 @@ import org.springframework.core.io.ClassPathResource;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.BDDMockito.when;
+import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
 /**
@@ -63,7 +63,7 @@ class Hazelcast4HazelcastHealthIndicatorTests {
 	@Test
 	void hazelcastDown() {
 		HazelcastInstance hazelcast = mock(HazelcastInstance.class);
-		when(hazelcast.executeTransaction(any())).thenThrow(new HazelcastException());
+		given(hazelcast.executeTransaction(any())).willThrow(new HazelcastException());
 		Health health = new HazelcastHealthIndicator(hazelcast).health();
 		assertThat(health.getStatus()).isEqualTo(Status.DOWN);
 	}

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/hazelcast/HazelcastHealthIndicatorTests.java

@@ -29,7 +29,7 @@ import org.springframework.core.io.ClassPathResource;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.BDDMockito.when;
+import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
 /**
@@ -59,7 +59,7 @@ class HazelcastHealthIndicatorTests {
 	@Test
 	void hazelcastDown() {
 		HazelcastInstance hazelcast = mock(HazelcastInstance.class);
-		when(hazelcast.executeTransaction(any())).thenThrow(new HazelcastException());
+		given(hazelcast.executeTransaction(any())).willThrow(new HazelcastException());
 		Health health = new HazelcastHealthIndicator(hazelcast).health();
 		assertThat(health.getStatus()).isEqualTo(Status.DOWN);
 	}

src/checkstyle/checkstyle.xml

@@ -41,9 +41,9 @@
 		</module>
  		<module name="com.puppycrawl.tools.checkstyle.checks.regexp.RegexpSinglelineJavaCheck">
  			<property name="maximum" value="0"/>
-			<property name="format" value="org\.mockito\.Mockito\.(when|doThrow|doAnswer)" />
+			<property name="format" value="org\.mockito\.(Mockito|BDDMockito)\.(when|doThrow|doAnswer)" />
 			<property name="message"
-				value="Please use BDDMockito imports." />
+				value="Please use BDD-style (given, when, then) using BDDMockito imports." />
 			<property name="ignoreComments" value="true" />
 		</module>
 		<module name="io.spring.javaformat.checkstyle.check.SpringJavadocCheck">