pgAdmin 4 commit: Fixed issues reported by SonarQube with tag 'bad-prac

Fixed issues reported by SonarQube with tag 'bad-practice'.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=6620f9263d4061ab01a19e71f9e22940db9bb826
Author: Aditya Toshniwal <aditya.toshniwal@enterprisedb.com>

Modified Files
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.../databases/schemas/tables/indexes/__init__.py   | 20 +++++-----
web/pgadmin/browser/static/js/error.js             | 46 +++++++++++-----------
web/pgadmin/static/js/alertify.pgadmin.defaults.js | 39 ++++++++----------
.../tools/import_export/static/js/import_export.js |  5 +--
4 files changed, 50 insertions(+), 60 deletions(-)