community avatar initials should not be rendered with user-avatar

[yqrashawn]

https://github.com/status-im/status-mobile/pull/16193#issuecomment-1594466429

some community avatars are rendered using user-avatar the one in the screenshot is a context-tag, and context-tag is using user-avatar to render initials https://github.com/status-im/status-mobile/blob/4a8764c790c7034e9b23ee5e3f08ba620617d516/src/quo2/components/tags/context_tag/view.cljs#L54

16193 tmp fix this by keeping initials logic in user-avatar (customization color community avatar is not working here)

now that user avatar images/initials are come from status-go we need to avoid using user-avatar component to render community avatar

better create a separate community avatar component similar to channel avatar and remove initials logic from user-avatar

[yqrashawn]

note: future community should all have user defined avatar so this issue might be out of scope