pgAdmin 4 commit: 1) Modified some labels and controls.

1) Modified some labels and controls.

2) Fixed issue where the same user is showing in SQL query.

3) Added SQL tab in the dialog.

refs #3893

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=8edd5946e55016b90be119f746ea79fd92201b26
Author: Rahul Shirsat <rahul.shirsat@enterprisedb.com>

Modified Files
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docs/en_US/images/role_drop_dialog.png             | Bin 57831 -> 57694 bytes
docs/en_US/images/role_drop_dialog_sql.png         | Bin 0 -> 24573 bytes
docs/en_US/images/role_reassign_dialog.png         | Bin 60164 -> 59219 bytes
docs/en_US/images/role_reassign_dialog_sql.png     | Bin 0 -> 25452 bytes
docs/en_US/role_reassign_dialog.rst                |  26 +++--
.../server_groups/servers/roles/__init__.py        |  60 +++++++++-
.../server_groups/servers/roles/static/js/role.js  |  44 +++++++-
.../servers/roles/tests/role_test_data.json        | 122 +++++++++++++++++++++
.../roles/tests/test_role_reassign_own_sql.py      |  71 ++++++++++++
9 files changed, 309 insertions(+), 14 deletions(-)