libsigc++: always run check

If the tests only take 3 seconds, just run them instead of providing an option.

Formula/libsigc++.rb

@@ -5,14 +5,10 @@ class Libsigcxx < Formula
   url 'http://ftp.gnome.org/pub/GNOME/sources/libsigc++/2.2/libsigc++-2.2.10.tar.bz2'
   sha256 'd3d810c2ad469edfb2d4db29643bef189b7613019eadbd4a72823af3c73c959c'
 
-  def options
-    [[ '--test', 'Verify the build during install with make check. (~3sec)' ]]
-  end
-
   def install
     system "./configure", "--prefix=#{prefix}", "--disable-dependency-tracking"
     system "make"
-    system "make check" if ARGV.include? '--test'
+    system "make check"
     system "make install"
   end
 end