pgAdmin 4 commit: Ensure that the superuser should be able to create da

Ensure that the superuser should be able to create database and role, as the superuser
overrides all the access restrictions.
Fixes #4792 Fixes #4878

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=f22134dabd6332f3faf851f2ddd96159c5bd7a85

Modified Files
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docs/en_US/release_notes_4_16.rst               | 2 ++
web/pgadmin/utils/driver/psycopg2/connection.py | 3 ++-
2 files changed, 4 insertions(+), 1 deletion(-)