[combobox] Ensure popup closes when tabbing out of popover

[atomiks]

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[pkg-pr-new[bot]]

vite-css-base-ui-example

pnpm add https://pkg.pr.new/mui/base-ui/@base-ui-components/react@3087

pnpm add https://pkg.pr.new/mui/base-ui/@base-ui-components/utils@3087

commit: d0d239a

[mui-bot]

Bundle size report

Bundle	Parsed size	Gzip size
@base-ui-components/react	🔺+101B(+0.02%)	🔺+19B(+0.01%)

Details of bundle changes

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