Support more types in UrlBuilder

What does this MR do?

This was extracted from !27428 (merged), and allows us to use Gitlab::UrlBuilder in more places.

• Add support for projects and groups.
• Add support for building path-only URLs.
• Reuse it in HasRepository#web_url.
• Remove state and turn the class into a singleton.
• Provide a default instance in presenters.
• Rewrite specs with parameterized table syntax.

The tweaks to the factories were extracted into !28778 (merged).

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team