gwt-time 1.4.20 (see 2.0.8 for GWT 2.9.0)

Enhancements

• Merge latest updates from https://github.com/ThreeTen/threetenbp
  • Update TZDB to 2022agtz
  • Remove unused HashMap's in ThaiBuddhistChronology (ThreeTen#155)
  • Fix repeating words (ThreeTen#153)
• Move build from Atlassian Bamboo to GitHub actions

Bugfixes

• None

Notes

• GWT 2.8.2 compatible release. This release is the same as https://github.com/foal/gwt-time/releases/tag/v2.0.8