pgAdmin 4 commit: Fix an issue where the save button was not getting en

Fix an issue where the save button was not getting enable when user revoke ADMIN option from Role privileges.
Issue: validation callback was missing in the control model.

Fixes #1302

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=1a84c356284f245bb790f2899c815770821428a5
Author: Murtuza Zabuawala <murtuza.zabuawala@enterprisedb.com>

Modified Files
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web/pgadmin/browser/server_groups/servers/roles/__init__.py         | 6 +++---
.../browser/server_groups/servers/roles/templates/role/js/role.js   | 3 +++
2 files changed, 6 insertions(+), 3 deletions(-)