Fix null ref in use slider

[MLoughry]

Current Behavior

When you click on a , and the component unmounts while the mouse button is down, and you then move the mosue while the mouse button is still down, there is a null-ref in useSlider()

New Behavior

There is no null-ref errror, as the window mouseMove events are cleaned up on unmount

Related Issue(s)

Fixes #24727

[codesandbox-ci]

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Latest deployment of this branch, based on commit 642bb52:

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

[size-auditor]

Asset size changes

Project	Bundle	Baseline Size	New Size	Difference
office-ui-fabric-react	fluentui-react-Slider	53.987 kB	54.053 kB	66 bytes

 Over Tolerance (1024 B)  Over Baseline  Below Baseline  New   Removed 1 kB = 1000 B

Baseline commit: d653291a07d843930da4023e599177686a1e6e1d (build)

[fabricteam]

📊 Bundle size report

_{🤖 This report was generated against d653291a07d843930da4023e599177686a1e6e1d}

[fabricteam]

Perf Analysis (@fluentui/react)

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
buttonNative	mount	91	109	5000	Possible regression

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
BaseButton	mount	767	762	5000
Breadcrumb	mount	2343	2341	1000
Checkbox	mount	2238	2220	5000
CheckboxBase	mount	1946	1938	5000
ChoiceGroup	mount	3822	3808	5000
ComboBox	mount	758	741	1000
CommandBar	mount	9221	8798	1000
ContextualMenu	mount	9692	9612	1000
DefaultButton	mount	921	947	5000
DetailsRow	mount	3027	3015	5000
DetailsRowFast	mount	2963	3029	5000
DetailsRowNoStyles	mount	2883	2894	5000
Dialog	mount	2549	2521	1000
DocumentCardTitle	mount	139	140	1000
Dropdown	mount	2765	2756	5000
FocusTrapZone	mount	1531	1541	5000
FocusZone	mount	1538	1512	5000
IconButton	mount	1367	1373	5000
Label	mount	334	323	5000
Layer	mount	3670	3676	5000
Link	mount	417	431	5000
MenuButton	mount	1185	1184	5000
MessageBar	mount	1944	1880	5000
Nav	mount	2666	2679	1000
OverflowSet	mount	995	995	5000
Panel	mount	2056	2077	1000
Persona	mount	807	820	1000
Pivot	mount	1115	1102	1000
PrimaryButton	mount	1074	1071	5000
Rating	mount	6540	6498	5000
SearchBox	mount	1078	1061	5000
Shimmer	mount	2452	2479	5000
Slider	mount	1663	1675	5000
SpinButton	mount	3845	3806	5000
Spinner	mount	394	401	5000
SplitButton	mount	2450	2391	5000
Stack	mount	456	467	5000
StackWithIntrinsicChildren	mount	1839	1829	5000
StackWithTextChildren	mount	4547	4509	5000
SwatchColorPicker	mount	9073	9029	5000
TagPicker	mount	1938	1932	5000
TeachingBubble	mount	73162	73000	5000
Text	mount	394	388	5000
TextField	mount	1134	1150	5000
ThemeProvider	mount	1015	1020	5000
ThemeProvider	virtual-rerender	710	722	5000
ThemeProvider	virtual-rerender-with-unmount	1580	1586	5000
Toggle	mount	696	717	5000
buttonNative	mount	91	109	5000	Possible regression