pgAdmin 4 commit: Do not dump the session data on the disk on every req

Do not dump the session data on the disk on every request.

Session object is updated, everytime a request is being served, and
that was forcing the session object dumped on the dist on every request.

On windows, it was causing issues on slower system on startup. Because -
windows file system locks the file, when it is opened by any
application. And, frequent requests on the pgAdmin main UI rendering
was causing issues, because of that.

In order to resolve the issue, we will not write the session data on
disk for every request, but - only after certain delay (in seconds),
from it was last written. It can be configured using the attribute
'PGADMIN_SESSION_DISK_WRITE_DELAY' in the configuration file,
default vaule for the delay is 10.
(i.e. 10 seconds)

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=d339d6b816a28c5947b2312a932c047773d7e350
Author: Harshal Dhumal <harshal(dot)dhumal(at)enterprisedb(dot)com>

Modified Files
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web/pgadmin/utils/session.py | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)