Allow $absolute to be passed to ValidateSignature Middleware

[craftyshaun]

When developing with Signed URL's today I tried to add the signed middleware to my routes which is an instance of Illuminate\Routing\Middleware\ValidSignature. Initially, I kept getting '401 - Invalid Signature' errors.

It wasn't until I dd()'d various internals I was able to see that Laravel was matching the whole URL when I was creating a signed URL with the $absolute option set to false as we use different subdomains in our app.

What I'd like to propose is the ability to pass the $absolute argument into the $request->hasValidSignature() call inside the middleware using a middleware parameter.

I'm happy to have a go at a PR for this feature assuming it passes a sense check from someone from the Laravel core team.

If this feature is not accepted them I'd like to suggest at the minimum a note be added to the docs that the ValidSignature middleware does not support non-absolute URL's out of the box.

[BrandonSurowiec]

This is already done for 8.x: #33137 It could be backported to 6.x if they allow it, but the PR was originally rejected due to BC, which is why I resubmitted it.