Always write data into the ruby-bench repository (#469)

Author: k0kubun

lib/argument_parser.rb

@@ -209,7 +209,7 @@ def have_zjit?(ruby)
   def default_args
     Args.new(
       executables: {},
-      out_path: File.expand_path("./data"),
+      out_path: File.expand_path("../data", __dir__),
       out_override: nil,
       harness: "harness",
       harness_explicit: false,