1.21.0

What's changed

Changes since 1.20.0

🚀 New features

• frontend#1978 - Hand RTL8710B firmware off to web.esphome.io and add it there (J. Nick Koston (@bdraco))
• frontend#1977 - Flash RTL8710B (AmebaZ) boards from the browser over Web Serial (J. Nick Koston (@bdraco))

🧹 Maintenance

• #2892 - Add the LN882H and RTL8710B flasher ids to the hand-off protocol (J. Nick Koston (@bdraco))

⬆️ Dependencies / CI

• #2890 - ci: bump CodSpeedHQ/action from 5.2.1 to 5.4.0 (Dependabot (@dependabot)[bot])