Code cleanup: remove superfluous call of the setToolTip method.

These calls were added while working on two separate tickets
 - EXT - 6027 ([TRANSLATED BUT IN EN] Bubble shown when you mouseover on system folder within Inventory > Library) (37baa70ea94b)
 - (EXT-6355) [TRANSLATED BUT IN EN] - Inventory, hovertext of system folders: hovertext isn?t localized. (80b6110ba41e)

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branch : product-engine