pgAdmin 4 commit: 1) Fixed an issue where an existing user is deleted a

1) Fixed an issue where an existing user is deleted and recreated again in the User Management dialog. Fixes #7618
2) Fixed preferences issue when changing themes.
3) Added validation for user names that already exist.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=ef912076697a5dd35ae968044fa71b4f27c25dfa

Modified Files
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web/pgadmin/static/js/helpers/ModalProvider.jsx            |  4 ++--
web/pgadmin/tools/user_management/__init__.py              | 13 ++++++-------
.../user_management/static/js/UserManagementDialog.jsx     | 14 ++++++++++++++
3 files changed, 22 insertions(+), 9 deletions(-)