[pgAdmin4][RM3936] - Fixes for feature test due to changes in pgadmin4

Please find here attached patch for the followings

i) Fixes for the query tool related test cases, the tab name convention is changed which is catered in the patch.

ii) The 'dependent' tab was not showing information until it is refreshed so handled it during automation(the issue was not reproducible manually).

iii) New locator file is created to store locators/xpaths.

iv) Changes in pgadmin_page file related to js.

 

Patch by :

          Usman & Aditya(aditya.toshniwal@enterprisedb.com)
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