Explicitly set $ruby_version to "" if no version number is given.

postmodern · postmodern · commit a0182af2c1bf · 2026-01-13T16:50:09.000-08:00
diff --git a/share/ruby-install/ruby-install.sh b/share/ruby-install/ruby-install.sh
@@ -95,6 +95,7 @@ function parse_ruby()
 			;;
 		*)
 			ruby="$string"
+			ruby_version=""
 			;;
 	esac
 
