pgAdmin 4 commit: 1) Added logic to set the appropriate default binary

1) Added logic to set the appropriate default binary path if DEFAULT_BINARY_PATH is
   set in the config and the user not updated the preferences.
2) Remove 'gpdb' from DEFAULT_BINARY_PATH.
3) Fixed API test cases.

refs #5370

Branches
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React_Porting
master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=07eb5418067a11541aad09259797fcdfa5c7206e

Modified Files
--------------
web/config.py                                      |  3 +-
web/pgadmin/browser/server_groups/servers/types.py | 51 +++++++++++++++++++++-
web/pgadmin/misc/__init__.py                       | 15 ++++---
web/pgadmin/static/js/backform.pgadmin.js          | 23 +---------
web/pgadmin/utils/__init__.py                      |  5 +++
web/pgadmin/utils/constants.py                     | 39 +++++++++++++++++
web/regression/python_test_utils/test_utils.py     | 11 +++--
web/regression/test_config.json.in                 |  3 +-
8 files changed, 112 insertions(+), 38 deletions(-)