can not create share group from share group snapshot

Repro:

- create a share group type if none is available, share network etc
- create a share group
- create a snapshot of share group
- try to create share group from snapshot

fails with "Unable to create a share group" right in the form, form is not submitted.

After some debugging, this looks like aftermath of
https://review.opendev.org/q/Id924fc55debdc38ae2131bf8cef396f28caa3e77

when we create a share group from snapshot, we fetch the share group type id of the original share group the snapshot was made of, and it is naturally a UUID, with dashes etc.

Then the transform_dashed_name is applied, which corrupts it, example

>>> transform_dashed_name("c6c70fa8-5c31-422a-a6ff-d585796aca89")
mm3ggnzqmzqtqljvmmztcljugizgcllbgztgmllegu4dknzzgzqwgyjyhe______

which then of course breaks the API request as there's no such share group type.