Fixed Overflow component when there's more then one children element

[ValentinaKozlova]

When there's more than one child component for the Overflow element then overflow items are still displayed.
Example:

<Overflow>
  <div>
    <div className={mergeClasses(styles.container, styles.resizableArea)}>
      {itemIds.map((i) => (
        <OverflowItem key={i} id={i}>
          <Button>Item {i}</Button>
        </OverflowItem>
      ))}

      <OverflowMenu itemIds={itemIds} />
    </div>
  </div>
</Overflow>

Previous Behavior

New Behavior

Related Issue(s)

• Fixes #

[codesandbox-ci]

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

[size-auditor]

Asset size changes

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

Baseline commit: 2bea5b29844ac124b923a40e20e135e5b25668c6 (build)

[fabricteam]

📊 Bundle size report

Unchanged fixtures

Package & Exports	Size (minified/GZIP)
react-components react-components: Button, FluentProvider & webLightTheme	67.994 kB 18.395 kB
react-components react-components: Accordion, Button, FluentProvider, Image, Menu, Popover	207.4 kB 57.516 kB
react-components react-components: FluentProvider & webLightTheme	38.819 kB 12.351 kB
react-overflow hooks only	11.214 kB 4.271 kB
react-portal-compat PortalCompatProvider	6.446 kB 2.185 kB

_{🤖 This report was generated against 2bea5b29844ac124b923a40e20e135e5b25668c6}

[fabricteam]

Perf Analysis (@fluentui/react-components)

No significant results to display.

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
Avatar	mount	921	911	5000
Button	mount	576	568	5000
Field	mount	1614	1639	5000
FluentProvider	mount	1179	1160	5000
FluentProviderWithTheme	mount	297	303	10
FluentProviderWithTheme	virtual-rerender	281	283	10
FluentProviderWithTheme	virtual-rerender-with-unmount	279	288	10
InfoButton	mount	201	206	5000
MakeStyles	mount	1293	1301	50000
Persona	mount	2286	2204	5000
SpinButton	mount	2004	1996	5000