pgAdmin 4 commit: Fix error while importing data to a table using Impor

Fix error while importing data to a table using Import/Export dialog and providing Not null columns option. Fixes
#4461.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=04357b7a55f758109e6bf7306950dbe9f659ea34
Author: Aditya Toshniwal <aditya.toshniwal@enterprisedb.com>

Modified Files
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docs/en_US/release_notes_4_13.rst                              |  1 +
web/pgadmin/tools/import_export/__init__.py                    | 10 +++-------
.../tools/import_export/templates/import_export/sql/cmd.sql    |  2 +-
3 files changed, 5 insertions(+), 8 deletions(-)