Add js checks in multiple files if data is undefined

Signed-off-by: Atul Pratap Singh <atulpratapsingh05@gmail.com>
Translated using Weblate (English (United Kingdom))

Currently translated at 100.0% (2768 of 2768)

[ci skip]
Merge remote-tracking branch 'origin/QA_4_2' into QA_4_2
Merge commit 'a020eac11a26977295cf2439ddd2e5b4af2c88fe'

Conflicts:
	js/config.js
	js/db_search.js
	js/functions.js
	js/makegrid.js
	js/server_privileges.js
	js/tbl_structure.js
Merge commit '01c7f4e3f1433fb7365413f4e8dc5fea57e8fd76'