Label (v8): convert tests to use testing-library

[TristanWatanabe]

Current Behavior

• v8 Label tests don't use testing-library

New Behavior

• Convert Label to fully use testing-library

Related Issue(s)

part of #21663

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit a2edf42:

Sandbox	Source
@fluentui/react 8 starter	Configuration
@fluentui/react-components 9 starter	Configuration

[fabricteam]

📊 Bundle size report

_{🤖 This report was generated against b1bdeac784560bddabdd6f71d76f1b752ae73a1a}

[size-auditor]

Asset size changes

Size Auditor did not detect a change in bundle size for any component!

Baseline commit: b1bdeac784560bddabdd6f71d76f1b752ae73a1a (build)

[fabricteam]

Perf Analysis (@fluentui/react)

No significant results to display.

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
BaseButton	mount	964	964	5000
Breadcrumb	mount	2749	2783	1000
Checkbox	mount	1510	1529	5000
CheckboxBase	mount	1320	1308	5000
ChoiceGroup	mount	4823	4848	5000
ComboBox	mount	1033	984	1000
CommandBar	mount	10617	10758	1000
ContextualMenu	mount	11997	12250	1000
DefaultButton	mount	1153	1170	5000
DetailsRow	mount	3838	3819	5000
DetailsRowFast	mount	3897	3895	5000
DetailsRowNoStyles	mount	3678	3666	5000
Dialog	mount	2242	2250	1000
DocumentCardTitle	mount	170	171	1000
Dropdown	mount	3363	3389	5000
FocusTrapZone	mount	1812	1845	5000
FocusZone	mount	1867	1887	5000
IconButton	mount	1794	1837	5000
Label	mount	357	372	5000
Layer	mount	2968	2975	5000
Link	mount	482	485	5000
MenuButton	mount	1523	1545	5000
MessageBar	mount	2229	2226	5000
Nav	mount	3390	3383	1000
OverflowSet	mount	1130	1148	5000
Panel	mount	2159	2233	1000
Persona	mount	846	871	1000
Pivot	mount	1495	1486	1000
PrimaryButton	mount	1358	1305	5000
Rating	mount	7904	7857	5000
SearchBox	mount	1327	1361	5000
Shimmer	mount	2496	2513	5000
Slider	mount	1955	1981	5000
SpinButton	mount	5134	5130	5000
Spinner	mount	452	457	5000
SplitButton	mount	3259	3242	5000
Stack	mount	556	550	5000
StackWithIntrinsicChildren	mount	2293	2343	5000
StackWithTextChildren	mount	5340	5383	5000
SwatchColorPicker	mount	11760	12000	5000
TagPicker	mount	2763	2787	5000
TeachingBubble	mount	99147	98255	5000
Text	mount	444	431	5000
TextField	mount	1464	1455	5000
ThemeProvider	mount	1218	1199	5000
ThemeProvider	virtual-rerender	662	673	5000
ThemeProvider	virtual-rerender-with-unmount	1926	1877	5000
Toggle	mount	819	799	5000
buttonNative	mount	116	128	5000