pgAdmin 4 commit: Add optional data point markers and mouse-overtoolti

Add optional data point markers and mouse-over tooltips to display values on graphs. Fixes #3514
Ensure queries are no longer executed when dashboards are closed. Fixes #3576

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=a74b9c96c1e699816fb9f93c9a54a5e7373deeac
Author: Aditya Toshniwal <aditya.toshniwal@enterprisedb.com>

Modified Files
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docs/en_US/release_notes_3_4.rst                   |   3 +
web/package.json                                   |   3 +-
web/pgadmin/browser/static/js/panel.js             |   9 +-
web/pgadmin/dashboard/__init__.py                  |  25 +++-
web/pgadmin/dashboard/static/js/charting.js        |  99 ++++++++++++++
web/pgadmin/dashboard/static/js/dashboard.js       | 147 +++++++++++++--------
.../javascript/dashboard/charting_spec.js          |  91 +++++++++++++
web/webpack.config.js                              |   1 +
web/webpack.test.config.js                         |   3 +
web/yarn.lock                                      |   6 +-
10 files changed, 324 insertions(+), 63 deletions(-)