pgAdmin 4 commit: Allow keyboard navigation of all controls on subnode

Allow keyboard navigation of all controls on subnode grids. Partially fixes #3919

Branch
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electron2

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=47447a709acf812680c6ef2c27597c6887e4fed4
Author: Ganesh Jaybhay <ganesh.jaybhay@enterprisedb.com>

Modified Files
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docs/en_US/keyboard_shortcuts.rst                  |  23 +++
docs/en_US/release_notes_4_11.rst                  |   1 +
.../browser/register_browser_preferences.py        |  15 ++
web/pgadmin/browser/static/js/keyboard.js          |   8 +
web/pgadmin/static/js/backform.pgadmin.js          |  19 +-
web/pgadmin/static/js/backgrid.pgadmin.js          | 226 +++++++++++++++++++--
web/pgadmin/static/js/dialog_tab_navigator.js      |  23 ++-
web/pgadmin/static/scss/_backgrid.overrides.scss   |   4 +
web/pgadmin/static/scss/_pgadmin.style.scss        |   9 +-
9 files changed, 296 insertions(+), 32 deletions(-)