databases/ladybug: Update 0.20.0 => 0.21.1

Changelogs:
https://github.com/LadybugDB/ladybug/releases/tag/v0.20.1
https://github.com/LadybugDB/ladybug/releases/tag/v0.20.2
https://github.com/LadybugDB/ladybug/releases/tag/v0.20.3
https://github.com/LadybugDB/ladybug/releases/tag/v0.20.4
https://github.com/LadybugDB/ladybug/releases/tag/v0.21.0
https://github.com/LadybugDB/ladybug/releases/tag/v0.21.1

PR: 298978
Sponsored by: UNIS Labs
MFH: 2026Q3

(cherry picked from commit 9db10da1e26179e6d5af4f9accac3242ea2c4288)