fix: Combobox v9 opens popup when typing in input

[smhigley]

Addresses one item of #25724

This was originally the intent, and was confirmed by the user study -- Combobox should open the popup when the user begins typing in the input.

[fabricteam]

📊 Bundle size report

Package & Exports	Baseline (minified/GZIP)	PR	Change
react-combobox Combobox (including child components)	78.244 kB 25.015 kB	78.297 kB 25.029 kB	53 B 14 B

Unchanged fixtures

Package & Exports	Size (minified/GZIP)
react-combobox Dropdown (including child components)	77.531 kB 24.927 kB
react-components react-components: Button, FluentProvider & webLightTheme	59.018 kB 16.371 kB
react-components react-components: Accordion, Button, FluentProvider, Image, Menu, Popover	186.456 kB 52.327 kB
react-components react-components: FluentProvider & webLightTheme	33.48 kB 11.037 kB
react-portal-compat PortalCompatProvider	5.857 kB 1.978 kB

_{🤖 This report was generated against 918de2a839052abfac8532f09e7dc5cdb180c574}

[size-auditor]

Asset size changes

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

Baseline commit: 918de2a839052abfac8532f09e7dc5cdb180c574 (build)

[fabricteam]

Perf Analysis (@fluentui/react-components)

No significant results to display.

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
Avatar	mount	1539	1576	5000
Button	mount	1143	1110	5000
FluentProvider	mount	1865	1891	5000
FluentProviderWithTheme	mount	751	748	10
FluentProviderWithTheme	virtual-rerender	706	691	10
FluentProviderWithTheme	virtual-rerender-with-unmount	746	743	10
MakeStyles	mount	2270	2266	50000
Persona	mount	3628	3550	5000
SpinButton	mount	2970	3026	5000

[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 0bbb411:

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

[fabricteam]

🕵 fluentuiv9 Open the Visual Regressions report to inspect the 3 screenshots

✅ There was 3 screenshots added, 0 screenshots removed, 1745 screenshots unchanged, 6 screenshots with different dimensions and 0 screenshots with visible difference.

unknown 3 screenshots

Image Name	Diff(in Pixels)	Image Type
Toolbar Converged.Large.Button Pressed.chromium.png	0	Added
Toolbar Converged.Large.Toggle On.chromium.png	0	Added
Toolbar Converged.Large.default.chromium.png	0	Added