keybase: Update to v6.6.0 (#8387)

**Summary**

Changes:
- Emoji 16 support
- Better sharing/push support
- Various bug fixes and performance improvements

**Test Plan**
- Sent a message
- Encrypted/decrypted a file
- Checked wallet status in Settings

**Checklist**

- [x] Package was built and tested against unstable
- [ ] This change could gainfully be listed in the weekly sync notes
once merged <!-- Write an appropriate message in the Summary section,
then add the "Topic: Sync Notes" label -->

Author: davidjharder