fix: mocked date for command Bar unit test case (#7270)

#### Details

Unit test case for details-view-command-bar.test is failing due to
mismatched dates between saved snapshot and rendered object. Rendered
object always takes the current date. Mocked the date in the test case
to return specific date instead of current date.

##### Motivation

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##### Context

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a later PR to handle? -->

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#### Pull request checklist
<!-- If a checklist item is not applicable to this change, write "n/a"
in the checkbox -->
- [n/a] Addresses an existing issue: #0000
- [x] Ran `yarn fastpass`
- [x] Added/updated relevant unit test(s) (and ran `yarn test`)
- [x] Verified code coverage for the changes made. Check coverage report
at: `<rootDir>/test-results/unit/coverage`
- [x] PR title *AND* final merge commit title both start with a semantic
tag (`fix:`, `chore:`, `feat(feature-name):`, `refactor:`). See
`CONTRIBUTING.md`.
- [n/a] (UI changes only) Added screenshots/GIFs to description above
- [n/a] (UI changes only) Verified usability with NVDA/JAWS

src/tests/unit/tests/DetailsView/components/details-view-command-bar.test.tsx

@@ -314,6 +314,10 @@ describe('DetailsViewCommandBar', () => {
     });
 
     test('renders report export dialog', async () => {
+        const originalDate = Date;
+        const mockDate = new Date('2024-03-07T12:00:00Z');
+        global.Date = jest.fn(() => mockDate) as unknown as typeof Date;
+        global.Date.now = jest.fn(() => mockDate.getTime()) as unknown as typeof Date.now;
         const props = getProps();
         useOriginalReactElements('DetailsView/components/report-export-button', [
             'ReportExportButton',
@@ -325,6 +329,7 @@ describe('DetailsViewCommandBar', () => {
         await userEvent.click(exportButton);
         expect(getMockComponentClassPropsForCall(ExportDialog, 2).isOpen).toBe(true);
         expect(renderResult.asFragment()).toMatchSnapshot('export dialog open');
+        global.Date = originalDate;
     });
 
     test('renders load assessment dialog', async () => {