OZG-7473 add types

Based on CR comment.

alfa-client/libs/admin/reporting-shared/src/lib/aggregation-mapping.service.spec.ts

@@ -96,7 +96,7 @@ describe('AggregationMappingService', () => {
   });
 
   describe('get', () => {
-    const stateResource = createStateResource(createAggregationMappingResource());
+    const stateResource: StateResource<AggregationMappingResource> = createStateResource(createAggregationMappingResource());
     beforeEach(() => {
       resourceService.get = jest.fn().mockReturnValue(of(stateResource));
     });
@@ -114,7 +114,7 @@ describe('AggregationMappingService', () => {
 
   describe('save', () => {
     const aggregationMapping: AggregationMapping = createAggregationMapping();
-    const stateResource = createStateResource(createAggregationMappingResource());
+    const stateResource: StateResource<AggregationMappingResource> = createStateResource(createAggregationMappingResource());
     beforeEach(() => {
       resourceService.save = jest.fn().mockReturnValue(of(stateResource));
     });