pgAdmin 4 commit: Ensure that users should be able to modify the REMOTE

Ensure that users should be able to modify the REMOTE_USER environment
variable as per their environment by introducing the new config parameter
WEBSERVER_REMOTE_USER.

Fixes #6953

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=d4697e8f1c33b1db5fea495e6997764dee1b0428
Author: Khushboo Vashi <khushboo.vashi@enterprisedb.com>

Modified Files
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docs/en_US/release_notes_6_2.rst      | 1 +
docs/en_US/webserver.rst              | 3 +++
web/config.py                         | 7 +++++++
web/pgadmin/authenticate/webserver.py | 6 +++++-
4 files changed, 16 insertions(+), 1 deletion(-)