SST-43 Return lost import

Author: KeyrisXdSnow

server/src/main/groovy/ish/oncourse/server/api/v1/service/impl/ClassCostApiImpl.groovy

@@ -11,13 +11,16 @@
 
 package ish.oncourse.server.api.v1.service.impl
 
-import javax.inject.Inject
-import static ish.oncourse.server.api.servlet.ApiFilter.validateOnly
 import ish.oncourse.server.api.service.ClassCostApiService
 import ish.oncourse.server.api.v1.model.ClassCostDTO
 import ish.oncourse.server.api.v1.service.ClassCostApi
+import ish.oncourse.server.cayenne.ClassCost
 import org.apache.cayenne.validation.ValidationException
 
+import javax.inject.Inject
+
+import static ish.oncourse.server.api.servlet.ApiFilter.validateOnly
+
 class ClassCostApiImpl implements ClassCostApi {
 
     @Inject