docs(angular): adding angular version to readme

Author: lillykoller

README.md

@@ -20,6 +20,7 @@ Shows the mapping between the angular version and our lib versions.
 
 | Angular Version | Lib Version                   |
 |-----------------|-------------------------------|
+| `^21`           | `^13`                         |
 | `^20`           | `^11 \|\| ^12`                |
 | `^19`           | `^7 \|\| ^8 \|\| ^9 \|\| ^10` | 
 | `^18`           | `^6`                          |