Log Message:
neomutt: update to 20200821.

2020-08-21  Richard Russon  <rich@flatcap.org>
* Bug Fixes
  - fix maildir flag generation
  - fix query notmuch if file is missing
  - notmuch: don't abort sync on error
  - fix type checking for send config variables
* Changed Config
  - `$sidebar_format` - Use `%D` rather than `%B` for named mailboxes
* Translations
  - 96% Lithuanian
  - 90% Polish