[HttpFoundation] fixed getClientIps() and getClientIp()

The order of IP addresses being returned by `getClientIps()` was incorrect. The data provider for the tests was confusing and some of the expectations were incorrect, so I cleaned that up as well.

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | yes
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | ~
| License       | MIT
| Doc PR        | ~