Refactor footer and home components; update image formats and improve text descriptions

src/app/home/home.component.spec.ts

@@ -6,7 +6,7 @@ describe('HomeComponent', (): void => {
   let component: HomeComponent;
   let fixture: ComponentFixture<HomeComponent>;
 
-  beforeEach(async () => {
+  beforeEach(async (): Promise<void> => {
     await TestBed.configureTestingModule({
       imports: [HomeComponent]
     })