Traffic Portal v2 CDNs detail page

[zrhoffman]

This PR adds the Traffic Portal v2 CDN detail page.

---

Which Traffic Control components are affected by this PR?

• Traffic Portal v2

What is the best way to verify this PR?

Run the unit tests and the end-to-end tests

PR submission checklist

• This PR has tests
• This PR has documentation
• This PR has a CHANGELOG.md entry
• This PR DOES NOT FIX A SERIOUS SECURITY VULNERABILITY (see the Apache Software Foundation's security guidelines for details)

[ocket8888]

Just like in TPv1, this form allows editing the ALL CDN, which - to my chagrin - ought not to be done because that's a special meta object. Similarly, TPv1 allows editing the root tenant (it'll never succeed because the API won't allow it, but the portal itself doesn't stop you from trying), however, in TPv2 you'll notice that all of the fields of the root tenant are read-only.

That's not, strictly speaking, the same situation, because the ALL CDN actually can be successfully updated i.e. the API allows it. Though that's honestly quite dangerous, so I suggest we not allow it through the UI.

[zrhoffman]

Rebased to get #7363

[zrhoffman]

Just like in TPv1, this form allows editing the ALL CDN, which - to my chagrin - ought not to be done because that's a special meta object. Similarly, TPv1 allows editing the root tenant (it'll never succeed because the API won't allow it, but the portal itself doesn't stop you from trying), however, in TPv2 you'll notice that all of the fields of the root tenant are read-only.

That's not, strictly speaking, the same situation, because the ALL CDN actually can be successfully updated i.e. the API allows it. Though that's honestly quite dangerous, so I suggest we not allow it through the UI.

That's a little out-of-scope for creating the CDN details page IMO, let's create a new GH Issue for it.

[zrhoffman]

Rebased to fix conflicts

[ocket8888]

The form needs error hints but that's systemic to TPv2 so it's unfair to require them in this PR.