feat(overflow-menu): add custom focus management

[emyarod]

Related Ticket(s)

carbon-design-system/carbon-for-ibm-dotcom#9807

Description

This PR addresses the focus management portion of the overflow menu enhancements epic. By adding [data-primary-focus] to an overflow menu item, the menu will focus on that item rather than the first valid item when the menu is opened

Changelog

Changed

• FocusMixin now accounts for primary focus selector

[ibmdotcom-bot]

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[ibmdotcom-bot]

Deploy preview created for Carbon Web Components:
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Built with commit: b174929a7ff8666761f9cfa0503baea26a375728

[ibmdotcom-bot]

Deploy preview created for Carbon Web Components - React:
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Built with commit: b174929a7ff8666761f9cfa0503baea26a375728

[ibmdotcom-bot]

Deploy preview created for Carbon Web Components - Angular:
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Built with commit: b174929a7ff8666761f9cfa0503baea26a375728