Describe the bug

If the user goes into the pg_catalogs and expands the procedure node then "raise_application_error" is also displayed but if the user tries to debug it, the user can do it, the debugger should be disabled for system catalogs

To Reproduce

Steps to reproduce the behavior:

1. Go to PostgreSQL_catalogs(pg_catlogs)
2. Right Click on a procedure3.  select debugger and click on click on debug
3. No result is displayed

Expected behavior

Debugger should be disabled on system catalogs.

Screenshots

Desktop (please complete the following information):
 - OS: [All]
 - Version: [tested on v6.21 and above]
 - Mode: [All]
 - Package type: [All]