Checks array key is defined before updating bookmarks

[NetStorm84]

Description (*)

This fixes an error when if a certain admin grid does not have filters then an error was being shown and changes to the grid were not saved, such as moving a column position.. This PR checks to see if certain array keys are set before doing a comparison on them.

Fixed Issues (if relevant)

1. Fixes Error on adminhtml popup product grids (e.g. adding Simple Product to Grouped Product) #38778

Manual testing scenarios (*)

Go to a grid that doesn't have filters and change the columns sort order by dragging a column to a new position

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[NetStorm84]

@magento run all tests