Add a format attribute to the common schema #7105
Description
Summary or User Story
Needed as part of pulibrary/dpul-collections#1043
We have genre but need format to extract that value from JSON-LD.
https://github.com/pulibrary/figgy/blob/main/app/models/schema/common.rb#L37C12-L37C17
Acceptance Criteria
- Format is a Schema::Common attribute