Pachli 2.8.3

New features:

- Show share sheet on long clicking links etc
- Show "copy" button for links etc in accessibility dialogs
- Add accessibility options for tabs
- Show a scheduled post's time
- Add "Don't ask again" when confirming the post's language

Fixes:

- Disable "Scheduled post" support on GoToSocial
- Show polls if editing scheduled posts
- Don't crash if a conversation has no participants

- Update Burmese, Finnish, Lithuanian, Spanish, Ukrainian translations