fix(NcAvatar): contacts menu is broken

[ShGKme]

☑️ Resolves

• Add missing imports
  • Regression from perf(utils): ensure only 64px or 512px avatars are loaded #6749
  • 
• Contacts menu is not opening
  • Incorrect merge conflict resolving in [next] chore(master): merge master into next #5158

  • Before	After

• Remove redundant check on unsubscribing
  • Missing backport from [stable8] fix(NcAvatar): skip user status request if hideStatus prop was provided #6780
• Do not execute a render function in a computed to check for an icon
  • For Vue 3 migration

🏁 Checklist

• ⛑️ Tests are included or are not applicable
• 📘 Component documentation has been extended, updated or is not applicable
• 2️⃣ Backport to stable8 for maintained Vue 2 version or not applicable