Fix method name typo

Author: shinokaro

lib/ocran/direction.rb

@@ -202,7 +202,7 @@ def construct(builder)
       # If requested, add all ruby standard libraries
       if @option.add_all_core?
         say "Will include all ruby core libraries"
-        ruby_library_path.each do |path|
+        ruby_core_library_dir.each do |path|
           # Match the load path against standard library, site_ruby, and vendor_ruby paths
           path.to_posix.match(RUBY_LIBRARY_PATH_REGEX) do |m|
             subdir = m[1]