net-im/toot: Update to 0.21.0

• Add new runtime dependencies
• Add more toot tests to the makefile
• Changelogs:
  • https://github.com/ihabunek/toot/releases/tag/0.20.0
  • https://github.com/ihabunek/toot/releases/tag/0.21.0

Reviewed by: krion
Approved by: krion (mentor)
Differential Revision: https://reviews.freebsd.org/D19377