[Tagging] Add Existing Tag to Additional Parent

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We know of existing examples where a sub-competency exists within one or more competencies. Currently, the add tag feature does not allow for any tag to be named the same as an existing tag at any level. Meaning, users cannot create a "Child A" under both "Parent A" and "Parent B." There is also no way to add existing tags to additional parents. The ability to add existing tags to another parent will be needed to allow for overlapping sub-competencies across multiple competencies.