pgAdmin 4 commit: 1) Fixes parallel test execution failures.

1) Fixes parallel test execution failures.
2) Added capability to pass browser-name via command line for parallel execution.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=34fbe756e854bc202c53abfa12e7257851415e7c
Author: Yogesh Mahajan <yogesh.mahajan@enterprisedb.com>

Modified Files
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web/pgadmin/feature_tests/file_manager_test.py     |  11 +-
.../feature_tests/query_tool_journey_test.py       |  20 ++-
web/pgadmin/feature_tests/query_tool_tests.py      |   1 +
.../xss_checks_panels_and_query_tool_test.py       |   5 +-
web/regression/python_test_utils/test_utils.py     |  19 ++-
web/regression/runtests.py                         | 178 +++++++++++----------
6 files changed, 134 insertions(+), 100 deletions(-)