Library Checks: Store library-api version with schema import

[prestoncabe]

This is needed to build the correct URLs for each endpoint.

the rool of the URLs include the version, e.g.:
https://library-api-v0-4-0---library-api-cnsoqyluna-uc.a.run.app/

for version 0.4.0.

Background:

• each implementation of each check on a benefit/screener will be of a particular version. Only way to upgrade to a new version (for now), is to delete/re-add that check.
• the current library-api version and all previous versions (for now) are deployed to Google Cloud Run and can be accessed (via a unique URL for each version) "forever".