pgAdmin 4 commit: Ensure JSON data isn't modified in-flight bypsycopg2

Ensure JSON data isn't modified in-flight by psycopg2 when using View/Edit data. Fixes #3600

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=59446bb4b5fdcea98351a80de3bb90ddca634326
Author: Aditya Toshniwal <aditya.toshniwal@enterprisedb.com>

Modified Files
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docs/en_US/release_notes_4_3.rst                   |  1 +
.../dashboard/sql/default/dashboard_stats.sql      | 10 +++----
web/pgadmin/static/js/slickgrid/editors.js         | 34 +++++++++++++++-------
.../tools/sqleditor/static/css/sqleditor.css       |  6 ----
.../tools/sqleditor/static/scss/_sqleditor.scss    | 17 ++++++++---
web/pgadmin/utils/driver/psycopg2/__init__.py      | 10 +------
web/pgadmin/utils/driver/psycopg2/typecast.py      |  9 ++++++
7 files changed, 53 insertions(+), 34 deletions(-)