Add compare header version to create_image_from_server helper

This PS uses `compare_version_header_to_response` in
`api_version_utils` in create_image_from_server to correctly parse
the image_id from the returned image, based on the microversion
in the response body.

According to the Nova docs for this API [0], the image_id is
located in location header for < 2.45 microversion but for
>= 2.45 it is located in resp.response['image_id'].

This PS also removes an unnecessary LOG.debug statement from
`compare_version_header_to_response`, pointed out by last comment in
this other PS [1].

[0] https://developer.openstack.org/api-ref/compute/#create-image-createimage-action
[1] Ib97e65cca468a09bbeaf68fcfe0e8192674a481e

Change-Id: I413a0b79f47ead94a94ac5cf862002eeb0b8543b
2 files changed