BUGFIX 'silverstripe/staticpublishqueue' user agent should be ignored

[mattclegg]

When using the silverstripe/silverstripe-staticpublishqueue module the REQUEST_URI is updated so what's used for the request will be different from what is defined in $_SERVER['REQUEST_URI'].

As the REQUEST_URI can no longer be relied on then it makes more sense to ignore the user agent for staticpublishqueue.

ref; https://github.com/silverstripe/silverstripe-staticpublishqueue/blob/master/src/Publisher.php#L82-L101

[axllent]

I don't generally like to include package-specific work-arounds, however this seems like the best solution here. Thanks for your input @mattclegg - I'll push through a new release shortly.

[mattclegg]

Yeah, I agree that it's not good to use a package-specific work-around. I've updated it to use a more generic approach; #12