pgAdmin 4 commit: Fixed some accessibility issues:

Fixed some accessibility issues:
1) Focus is not visible while navigating through top navbar menu items(File, Object, Tools)
2) In preference dialog wherever access key is used for a shortcut declaration, unable to get out of the textbox.
3) Focus is not visible for the links on the dashboard

Fixes #7046

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=e30cbe2579e49ecb03ae3244424f9c8b88bf40d3
Author: Ganesh Jaybhay <ganesh(dot)jaybhay(at)enterprisedb(dot)com>

Modified Files
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docs/en_US/release_notes_6_3.rst | 1 +
web/pgadmin/static/js/alertify.pgadmin.defaults.js | 17 +++++++++++++++++
web/pgadmin/static/scss/_jsoneditor.overrides.scss | 4 ----
3 files changed, 18 insertions(+), 4 deletions(-)