FindPkgConfig: ignore whitespace separators in version check
The regex used to split up the version if it contains an operator fails if the string contains whitespaces. Resulting in an extra whitespace after the package name and before the package version leading to breakage in pkgconf and thus webkit-gtk.
See: https://github.com/pkgconf/pkgconf/issues/317 https://bugs.webkit.org/show_bug.cgi?id=261125 https://bugs.gentoo.org/913644