pgAdmin 4 commit: Added multiple drop/delete functionality for the tabl

Added multiple drop/delete functionality for the table constraints. Fixes #3900

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=6e5dbf7beb251d685788e08de477b5e17c50ed94
Author: Khushboo Vashi <khushboo.vashi@enterprisedb.com>

Modified Files
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docs/en_US/release_notes_4_21.rst                  |   1 +
.../schemas/tables/constraints/__init__.py         |  47 +++++++
.../constraints/check_constraint/__init__.py       |   3 +
.../constraints/exclusion_constraint/__init__.py   |   3 +
.../tables/constraints/foreign_key/__init__.py     |   3 +
.../constraints/index_constraint/__init__.py       |   3 +
.../tables/constraints/static/js/constraints.js    |   4 +-
.../tests/test_constraint_delete_multiple.py       | 137 +++++++++++++++++++++
web/pgadmin/browser/static/js/collection.js        |   8 +-
9 files changed, 206 insertions(+), 3 deletions(-)