fix(build): switch to isar next to fix ubuntu noble builds

The version of Isar we were on is trying to forcibly install the usrmerge
package while it was removed in Ubuntu Noble. This was fixed upstream in
the next branch: switched to it for the time being.

See: https://groups.google.com/g/isar-users/c/c_d8103JlRY
Signed-off-by: Cedric Hombourger <[email protected]>

kas/common/base.yml

@@ -21,7 +21,7 @@ repos:
       meta-isar:
   isar:
     url: https://github.com/ilbers/isar.git
-    commit: fe7f6a94ebc040fd1220f03056e2d6312b48f25d
+    commit: 483093e11cd722f0c88dc2fcbed1e937fc0abb60
     layers:
       meta:
       meta-isar: