Add Tigera Installation Registry to Versions Catalogue Schema

[drewwalters96]

Problem description (if applicable)
The Tigera Operator includes a document of kind: Installation that allows users to change the location of the container image repository used for deployment of Tigera images. This pattern does not fit our versions catalogue schema because we typically specify the location of each image individually rather than a repository that contains all of the images a particular operator will use.

Proposed change
We should include a new section in the versions catalogue schema, similar to the helm repository section, that allows us to catalogue container image repositories.

[shon-phand]

I can start working on this issue, please assign it to me

[eak13]

@shon-phand you've been assigned. Thanks.

[shon-phand]

https://review.opendev.org/c/airship/airshipctl/+/798942