Propagate Groovy's null-safe operator in tests.

No functional changes.

Author: php-coder

src/test/groovy/ru/mystamps/web/service/FilesystemImagePersistenceStrategyTest.groovy

@@ -63,7 +63,7 @@ class FilesystemImagePersistenceStrategyTest extends Specification {
 			strategy.save(multipartFile, imageInfoDto)
 		then:
 			1 * strategy.writeToFile(_ as MultipartFile, { Path path ->
-				assert path.parent.toString() == expectedDirectoryName
+				assert path?.parent?.toString() == expectedDirectoryName
 				return true
 			}) >> { }
 	}
@@ -78,7 +78,7 @@ class FilesystemImagePersistenceStrategyTest extends Specification {
 			strategy.save(multipartFile, imageInfoDto)
 		then:
 			1 * strategy.writeToFile(_ as MultipartFile, { Path path ->
-				assert path.fileName.toString() == expectedFileName
+				assert path?.fileName?.toString() == expectedFileName
 				return true
 			}) >> { }
 	}

src/test/groovy/ru/mystamps/web/service/SeriesImportServiceImplTest.groovy

@@ -94,10 +94,10 @@ class SeriesImportServiceImplTest extends Specification {
 			Integer result = service.addRequest(form, expectedUserId)
 		then:
 			1 * seriesImportDao.add({ ImportSeriesDbDto request ->
-				assert request.url == expectedUrl
-				assert request.status == SeriesImportRequestStatus.UNPROCESSED
+				assert request?.url == expectedUrl
+				assert request?.status == SeriesImportRequestStatus.UNPROCESSED
 				assert DateUtils.roughlyEqual(request?.requestedAt, new Date())
-				assert request.requestedBy == expectedUserId
+				assert request?.requestedBy == expectedUserId
 				assert DateUtils.roughlyEqual(request?.updatedAt, new Date())
 				return true
 			}) >> expectedResult
@@ -368,7 +368,7 @@ class SeriesImportServiceImplTest extends Specification {
 			service.saveParsedData(expectedRequestId, parsedData)
 		then:
 			1 * eventPublisher.publishEvent({ ParsingFailed event ->
-				assert event.requestId == expectedRequestId
+				assert event?.requestId == expectedRequestId
 				return true
 			})
 	}