update-version in k_doc-0.0.38

- old
+ new

@@ -28,6 +28,6 @@
 end
 
 output.push('')
 
 printf "%-25<label>s : %<version>s\n", label: 'GEM VERSION', version: version
-File.open('lib/k_doc/version.rb', 'w+') { |f| f.write(output.join("\n")) }
+File.write('lib/k_doc/version.rb', output.join("\n"))