[pgAdmin4][RM3294] User need to reset the layout to see the changed preferences parameters

Hi Hackers,

Attached is the patch for making preferences realtime and applying without
reseting the layout. Please note, the patch is only for one module - SQL
Editor and is the first part for the RM. There are lot of changes to be
done to cover all and hence sending in parts. This will not affect/break
existing code. Further patches will cover other modules.

Highlights of this patch include:
- Changes will affect SQL Editors in Create dialog boxes, SQL tab of the
main screen, Query tool, History entries in the query tool, Query tool
opened in New Tab/Window
- All the components of SQL editor will refer to single source of
preferences which is cached in the Browser object. All other redundant ajax
get preference calls are removed.
- SQL editor will not refer template JS variables anymore, once all the
references are removed the template variables will also be removed.
- Code refactoring wherever possible.
- Covered JS test cases wherever possible.

Request you to kindly review.

--
Thanks and Regards,
Aditya Toshniwal
Software Engineer | EnterpriseDB Software Solutions | Pune
"Don't Complain about Heat, Plant a tree"