Extract container registry page common components

What does this MR do and why?

Closes: gitlab-jh/gitlab#524 . Reference link: gitlab-jh&5289

Extract cli_commands.vue and tags_loader.vue to app/assets/javascripts/packages_and_registries/shared/components/ as common components.

Screenshots or screen recordings

Just code refactoring, no page changes involved.

MR acceptance checklist

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