pgAdmin 4 commit: Add feature tests for Backup/Restore andMaintenance.

Add feature tests for Backup/Restore and Maintenance. Fixes #3206

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=81312d17e280fabd5c77bf4a5e3b8c1ab93f1637
Author: Khushboo Vashi <khushboo.vashi@enterprisedb.com>

Modified Files
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.../pg_utilities_backup_restore_test.py            | 149 +++++++++++++++++++++
.../feature_tests/pg_utilities_maintenance_test.py | 109 +++++++++++++++
web/regression/runtests.py                         |   2 +-
3 files changed, 259 insertions(+), 1 deletion(-)