* gnu/packages/ruby.scm (ruby-nokogiri): Update to 1.15.2.
[source]<uri>: Use Git repository.
<patches>: apply a patch to disable unneeded test setups.
[arguments]: Enable check by running plain minitest.
[home-page]: Update to current URL.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>
