fix: Add focus state to toggle and clear icon button

What does this MR do?

This MR adds visual focus to the toggle and clear icon button elements for tab accessibility. It also removes a CSS outline value for the badge component which is unnecessary since it is not focusable.

Screenshots

Screen_Recording_2020-11-26_at_5.22.29_pm

Does this MR meet the acceptance criteria?

Conformity

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• GitLab UI's contributing guidlines.
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• Added the ~"component:*" label(s) if applicable.

Security

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• Label as security and @ mention @gitlab-com/gl-security/appsec
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