docs: update compatibility table

Author: nacho-vazquez

packages/docs/lumberjack-docs-app/docs/compatibility.md

@@ -7,6 +7,7 @@ Refer to the following table to determine which version of Lumberjack is compati
 
 | Angular version | Lumberjack version |
 | --------------- | ------------------ |
+| 20.x            | 20.x               |
 | 19.x            | 19.x               |
 | 18.x            | 18.x               |
 | 17.x            | 17.x               |