pgAdmin 4 commit: Allow screen-reader to read label & description of no

Allow screen-reader to read label & description of non-textable elements. Fixes #4762.
Allow screen-reader to identify the alert errors. Fixes #4763

Added role alertdialog for confirm and alert dialog.
Added role status for all status bars/banners.
Added role alert for error bars.
Added aria-labelledby for charts on each dashboard.
Added tabindex for each chart so that it is navigable using tab key.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=f167d77b61a4442f68dab4b3bdde5641bc20fada
Author: Nagesh Dhope <nagesh(dot)dhope(at)enterprisedb(dot)com>

Modified Files
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docs/en_US/release_notes_4_18.rst | 2 ++
.../servers/templates/servers/password.html | 2 +-
.../servers/templates/servers/tunnel_password.html | 2 +-
web/pgadmin/browser/static/js/browser.js | 8 +++---
web/pgadmin/browser/static/js/collection.js | 2 +-
web/pgadmin/browser/static/js/node.js | 6 ++---
web/pgadmin/browser/static/js/wizard.js | 4 +--
.../templates/dashboard/database_dashboard.html | 20 +++++++--------
.../templates/dashboard/server_dashboard.html | 20 +++++++--------
web/pgadmin/static/js/alertify.pgadmin.defaults.js | 29 +++++++++++++++++++---
web/pgadmin/static/js/sqleditor/filter_dialog.js | 2 +-
.../static/js/sqleditor/history/query_history.js | 2 +-
.../tools/datagrid/templates/datagrid/index.html | 1 +
web/pgadmin/tools/debugger/static/js/direct.js | 5 ++--
web/pgadmin/tools/sqleditor/static/js/sqleditor.js | 2 +-
15 files changed, 66 insertions(+), 41 deletions(-)