pgAdmin 4 commit: Modifies the way to execute feature tests in parallel

Modifies the way to execute feature tests in parallel and it should be configured in Server Mode.

Branches
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React_Porting
master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=2d58f60a53aadc07bf471102778e1089fd2239a2
Author: Yogesh Mahajan <yogesh.mahajan@enterprisedb.com>

Modified Files
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web/pgadmin/feature_tests/browser_tool_bar_test.py |   2 +
web/pgadmin/feature_tests/file_manager_test.py     |  26 +-
.../feature_tests/table_ddl_feature_test.py        |   4 +-
web/pgadmin/utils/route.py                         |   3 +
web/regression/README                              |   3 +-
web/regression/feature_utils/base_feature_test.py  |   4 +-
web/regression/feature_utils/pgadmin_page.py       |  23 +-
web/regression/python_test_utils/test_utils.py     |  28 ++-
web/regression/runtests.py                         | 272 +++++++++++----------
9 files changed, 219 insertions(+), 146 deletions(-)