pgAdmin 4 commit: Ensure that Backup and Restore should work on shared

Ensure that Backup and Restore should work on shared servers as some cases were failing due to initial changes.

Fixes #6385

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=8ae8fea6d2c4198af96e7bf380c2f5c108a32ed9
Author: Pradip Parkale <pradip.parkale@enterprisedb.com>

Modified Files
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docs/en_US/release_notes.rst                       |  1 +
docs/en_US/release_notes_5_2.rst                   |  3 +-
docs/en_US/release_notes_5_3.rst                   | 20 +++++++++++++
web/migrations/versions/c6974f64df08_.py           | 28 ++++++++++++++++++
.../browser/server_groups/servers/__init__.py      |  5 ++--
web/pgadmin/model/__init__.py                      |  7 ++++-
web/pgadmin/tools/backup/__init__.py               | 34 ++++------------------
web/pgadmin/tools/maintenance/__init__.py          | 28 ++++--------------
web/pgadmin/tools/restore/__init__.py              | 33 ++++-----------------
web/pgadmin/utils/__init__.py                      | 11 +++++++
10 files changed, 88 insertions(+), 82 deletions(-)