Remove redundant jstree script from search form

[colemanw]

Overview

Fixes a 404 on an unnecessary script.

Before

Tag popup works on search forms because the unneeded script could not be found.

After

Tag popup works on search forms because the unneeded script is removed.

Technical Details

#13128 fixed the old script interfering with the tag popup; turns out the correct script was loading from within the popup and doesn't need to be added to search forms at all.

[civibot]

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