pgAdmin 4 commit: Add Python API tests for execution of external utilit

Add Python API tests for execution of external utilities such as pg_dump.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=d1902cd63984c42385a19e8c224226fc3c3023c6
Author: Khushboo Vashi <khushboo(dot)vashi(at)enterprisedb(dot)com>

Modified Files
--------------
web/pgadmin/tools/backup/__init__.py | 33 +-
web/pgadmin/tools/backup/tests/__init__.py | 0
.../tests/test_backup_create_job_unit_test.py | 454 +++++++++++++++++++++
.../tools/backup/tests/test_backup_message.py | 147 +++++++
.../tools/backup/tests/test_backup_utils.py | 119 ++++++
.../tools/backup/tests/test_batch_process.py | 213 ++++++++++
.../tools/backup/tests/test_create_backup_job.py | 65 +++
web/pgadmin/tools/maintenance/tests/__init__.py | 0
.../tests/test_batch_process_maintenance.py | 155 +++++++
.../tests/test_create_maintenance_job.py | 136 ++++++
.../tests/test_maintenance_create_job_unit_test.py | 190 +++++++++
.../maintenance/tests/test_maintenance_message.py | 121 ++++++
web/pgadmin/tools/restore/__init__.py | 27 +-
web/pgadmin/tools/restore/tests/__init__.py | 0
.../tools/restore/tests/test_batch_process.py | 155 +++++++
.../tools/restore/tests/test_create_restore_job.py | 201 +++++++++
.../tests/test_restore_create_job_unit_test.py | 314 ++++++++++++++
.../tools/restore/tests/test_restore_message.py | 77 ++++
web/regression/python_test_utils/test_utils.py | 74 +++-
web/regression/runtests.py | 7 +-
web/regression/test_config.json.in | 7 +-
21 files changed, 2455 insertions(+), 40 deletions(-)