pgAdmin 4 commit: Automatically expand child nodes as well as the selec

Automatically expand child nodes as well as the selected node on the treeview if there is only one. Fixes #3559

This also ensure the browser state is cleared if the save interval is set to -1.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=17694ab467cccf090e425cadb6238c31548869ca
Author: Khushboo Vashi <khushboo(dot)vashi(at)enterprisedb(dot)com>

Modified Files
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docs/en_US/images/preferences_browser_display.png | Bin 83195 -> 248805 bytes
docs/en_US/preferences.rst | 6 ++++++
.../browser/register_browser_preferences.py | 10 ++++++++++
web/pgadmin/browser/static/js/node.js | 9 +++++++++
web/pgadmin/settings/__init__.py | 21 ++++++++++++++++++++-
.../static/js/tree/pgadmin_tree_save_state.js | 20 ++++++++++++++++++++
6 files changed, 65 insertions(+), 1 deletion(-)