[skip ci] Update changelogs for v0.20.0-rc.1 release

GitOrigin-RevId: 3643f288d64ea7af0b62b087da1db6654e75c0e6

Author: github-actions[bot]

CHANGELOG.md

@@ -5,6 +5,7 @@ Mapbox welcomes participation and contributions from everyone.
 ## main
 
 * Fix incorrect positioning of map ornaments when multiple ornaments are placed in the same corner.
+## 11.20.0-rc.1 - 03 March, 2026
 
 ## 11.19.0 - 24 February, 2026