Corrected tag_id parameter description to refer cases

[kainuk]

The description for the tag_id parameter should be
"Find cases with specified tags."
instead of
"Find activities with specified tags."

(See https://lab.civicrm.org/dev/core/issues/361)

[civibot]

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[mattwire]

Change looks fine, but I can't see how you would actually tag a case? @kainuk

[colemanw]

@mattwire first you have to create some tags that apply to cases, then the case UI lets you tag the case.