Add 4.3 to the version list

Part of the 4.3 release tasks the [week before the release](https://moodledev.io/general/development/process/release#1-week-prior)

Author: junpataleta

.github/workflows/publish-apidocs.yml

@@ -1,8 +1,8 @@
 name: Generate API docs and publish to Github Pages
 
 env:
-  BRANCHLIST: "MOODLE_39_STABLE MOODLE_311_STABLE MOODLE_400_STABLE MOODLE_401_STABLE MOODLE_402_STABLE master"
-  VERSIONLIST: "3.9 3.11 4.00 4.1 4.2 master"
+  BRANCHLIST: "MOODLE_39_STABLE MOODLE_311_STABLE MOODLE_400_STABLE MOODLE_401_STABLE MOODLE_402_STABLE MOODLE_403_STABLE master"
+  VERSIONLIST: "3.9 3.11 4.00 4.1 4.2 4.3 master"
 
 on:
   schedule: