Hints for qtox in main

Hints

• asv-summary-has-dot-suffix
  io.github.qtox.qTox.appdata.xml:9 - Powerful Tox chat client that follows the Tox design guidelines.
  The component summary should not end with a dot (`.`).
• asv-description-first-para-too-short
  io.github.qtox.qTox.appdata.xml:11 - A New Kind of Instant Messaging
  The first `description/p` paragraph of this component might be too short (< 80 characters). Please consider starting with a longer paragraph to improve how the description looks like in software centers and to provide more detailed information on this component immediately in the first paragraph.