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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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=4cbc1f2f59192f6461cfeea96aec2d3ee5df5f06
Author: Ganesh Jaybhay <ganesh(dot)jaybhay(at)enterprisedb(dot)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(-)