ruby: clean up extraction

There are no errors extracting the source, so just let the default
extraction do its thing.

ruby/PKGBUILD

@@ -30,7 +30,6 @@ sha256sums=('018d59ffb52be3c0a6d847e22d3fd7a2c52d0ddfee249d3517a0c8c6dbfa70af'
             'a4ec80d3da58969068112a26cc2a40eee0c6052ac61d789a84b6e5d74ef9246a'
             'd37409413b40e560a9d0e8977e711a6f47e7e92ef8dea8b85dee7e7784a47524'
             'd9494f491b031992d65eee7cfd78635882d56da602516654b3a77cf3dc19fe96')
-noextract=(ruby-${pkgver}.tar.xz)
 
 # Helper macros to help make tasks easier #
 apply_patch_with_msg() {
@@ -56,9 +55,6 @@ del_file_exists() {
 
 
 prepare() {
-  [[ -d ${srcdir}/ruby-${pkgver} ]] && rm -rf ${srcdir}/ruby-${pkgver}
-  tar -xf ${srcdir}/ruby-${pkgver}.tar.xz -C ${srcdir} || true
-
   cd ${srcdir}/ruby-${pkgver//_/-}
   apply_patch_with_msg 2.5.0-cygwin-configure.patch
   apply_patch_with_msg_p2 2.4.0-cygwin-rubygems.patch