v3.0.0

What's Changed

• Full Ruby 3.0 support: #919 (cjcolvar)
• Fixed Ruby 2.7.x support: #916 (tpendragon), #918
  (jrgriffiniii)
• Dropped support for Ruby 2.5.x: #916 (tpendragon)
• see previous 3.0.0 beta release notes for further changes