Increase page size based on metadata database state

What does this MR do and why?

Increases page size to 20 based on metadata database state for image list and tags list views.

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

How to set up and validate locally

1. Simulate SaaS instance https://docs.gitlab.com/ee/development/ee_features.html#simulate-a-saas-instance

2. Setup container registry https://gitlab.com/gitlab-org/gitlab-development-kit/blob/main/doc/howto/registry.md

3. Test out pagination with

   ContainerRegistry::GitlabApiClient.supports_gitlab_api?

   set to true (20 page size) vs false (10 page size)

Related to #467374 (closed)