test: remove unnecessary test calls (#32396)

Removes calls to `TestBed.configureTestingModule` since they aren't necessary.

(cherry picked from commit 06c78b4)

Author: crisbeto

docs/src/app/shared/documentation-items/documentation-items.spec.ts

@@ -8,7 +8,6 @@ describe('DocViewer', () => {
   let docsItems: DocumentationItems;
 
   beforeEach(() => {
-    TestBed.configureTestingModule({});
     docsItems = TestBed.inject(DocumentationItems);
   });
 

docs/src/app/shared/guide-items/guide-items.spec.ts

@@ -5,7 +5,6 @@ describe('GuideItems', () => {
   let guideItems: GuideItems;
 
   beforeEach(waitForAsync(() => {
-    TestBed.configureTestingModule({});
     guideItems = TestBed.inject(GuideItems);
   }));
 

src/aria/combobox/combobox.spec.ts

@@ -55,7 +55,6 @@ describe('Combobox', () => {
     function setupCombobox(
       opts: {readonly?: boolean; filterMode?: 'manual' | 'auto-select' | 'highlight'} = {},
     ) {
-      TestBed.configureTestingModule({});
       fixture = TestBed.createComponent(ComboboxListboxExample);
       const testComponent = fixture.componentInstance;
 
@@ -608,7 +607,6 @@ describe('Combobox', () => {
     function setupCombobox(
       opts: {readonly?: boolean; filterMode?: 'manual' | 'auto-select' | 'highlight'} = {},
     ) {
-      TestBed.configureTestingModule({});
       fixture = TestBed.createComponent(ComboboxTreeExample);
       const testComponent = fixture.componentInstance;
 

src/aria/menu/menu.spec.ts

@@ -476,7 +476,6 @@ describe('Menu Trigger Pattern', () => {
   };
 
   function setupMenu() {
-    TestBed.configureTestingModule({});
     fixture = TestBed.createComponent(MenuTriggerExample);
     fixture.detectChanges();
     getItem('Apple')?.focus();