pgAdmin 4 commit: Simplify cookie domain/path settings,per discussion.

Simplify cookie domain/path settings, per discussion. Instead of trying to be smart, just let the user specify them in
theconfig, e.g. 

COOKIE_DEFAULT_DOMAIN = None
SESSION_COOKIE_DOMAIN = None

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=413709fc78f5d671ade9bea7975912a5f1fa4110
Author: Khushboo Vashi <khushboo.vashi@enterprisedb.com>

Modified Files
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web/config.py                       |  4 ++--
web/pgadmin/__init__.py             | 11 ++---------
web/pgadmin/browser/__init__.py     |  3 ++-
web/pgadmin/preferences/__init__.py |  3 ++-
4 files changed, 8 insertions(+), 13 deletions(-)