pgAdmin 4 commit: Added support for Reassign/Drop Owned for login roles

Added support for Reassign/Drop Owned for login roles. Fixes #3893

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=5fe52b9cfec6d283724dfc5877caaf1da729daf9
Author: Rahul Shirsat <rahul.shirsat@enterprisedb.com>

Modified Files
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docs/en_US/images/role_drop_dialog.png             | Bin 0 -> 57831 bytes
docs/en_US/images/role_reassign_dialog.png         | Bin 0 -> 60164 bytes
docs/en_US/managing_cluster_objects.rst            |   3 +-
docs/en_US/release_notes_5_5.rst                   |   1 +
docs/en_US/role_reassign_dialog.rst                |  39 ++
.../server_groups/servers/roles/__init__.py        | 127 +++++-
.../server_groups/servers/roles/static/js/role.js  | 432 ++++++++++++++++++++-
.../templates/roles/sql/9.4_plus/reassign_own.sql  |  13 +
.../servers/roles/tests/role_test_data.json        | 127 ++++++
.../servers/roles/tests/test_role_reassign_own.py  |  99 +++++
.../server_groups/servers/roles/tests/utils.py     |   7 +-
11 files changed, 841 insertions(+), 7 deletions(-)