[12.X] Fix Http::preventStrayRequests error propagation when using Http::pool

[LeTamanoir]

When testing code that uses Http::pool via the Http::fake and Http::preventStrayRequests the error won't be propagated correctly, for example if you forget to fake a path you will get this kind of error:

Illuminate\Http\Client\PendingRequest::{closure:Illuminate\Http\Client\PendingRequest::makePromise():994}(): Argument #1 ($e) must be of type OutOfBoundsException|GuzzleHttp\Exception\TransferException, RuntimeException given, called in /[REDACTED]/vendor/guzzlehttp/promises/src/RejectedPromise.php on line 49

with the changes I propose you should get the following:

Attempted request to [your/route/...] without a matching fake.

[LeTamanoir]

I was not sure if I should have stayed with the RuntimeException + adding a regex check for the error message content in the PendingRequest callback.

Changing the exception class might be breaking for some strange code out there in the wild haha,
but considering it still inherits RuntimeException and Http::fake is only meant for testing I guess it's fine...

WDYT guys ?