Support Mastodon's poll feature

[Tsukimoe]

Expected behavior

The poll function is properly displayed in the Mastodon site

Actual behavior

Posts with poll do not display poll content, and ordinary text content is displayed normally. (missing votes)

Steps to reproduce

Extra info

https://mstdn.jp/@tsukimoe/109290884039938216 Android version: (version code here) 12 Network type:

• [ ] Cellular
• [x] Wi-Fi

App version: (version code here) 4.1.7 Build variant:

• [x] Google
• [ ] F-Droid

Micro-blogging service:

• [ ] Twitter
• [ ] Fanfou
• [ ] GNU Social / StatusNet
• [x] Mastodon

App settings:

• [ ] Custom API
• [ ] Custom consumer key/secrets
• [ ] Official keys
• [ ] Using Thumbor
• [ ] Connected through proxy
• [x] Media preview enabled