small cleanup

Author: chiaramapellimt

service/src/test/java/uk/nhs/adaptors/gp2gp/ehr/mapper/AgentDirectoryMapperTest.java

@@ -4,6 +4,7 @@
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.when;
+import static org.mockito.Mockito.reset;
 import static uk.nhs.adaptors.gp2gp.utils.IdUtil.buildReference;
 
 import org.hl7.fhir.dstu3.model.Bundle;
@@ -56,6 +57,10 @@ void setUp() {
     @AfterEach
     void tearDown() {
         messageContext.resetMessageContext();
+        messageContext = null;
+        agentDirectoryMapper = null;
+        fhirParseService = null;
+        reset(randomIdGeneratorService, agentPersonMapper);
     }
 
     private Answer<String> answerWithObjectId() {