Add lucide icons to avatar

[joyenjoyer]

Closes INSTUI-4864

Test: Try all these icon adding options with Avatar and check whether size and color passed to the icon correctly. Also check how changing theme impact the rendered component.

renderIcon={AlarmClockInstUIIcon} // reference to icon
renderIcon={<AlarmClockInstUIIcon />} // icon as React component
renderIcon={()=><AlarmClockInstUIIcon />} // icon as React component returned by an arrow function 

[github-actions[bot]]

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[joyenjoyer]

@matyasf I answered the comments and did changes where they were needed, please check the PR again.