CONTRIBUTING.md in stackdriver-0.20.1 vs CONTRIBUTING.md in stackdriver-0.21.0

- old
+ new

@@ -22,11 +22,11 @@
 ## Setup
 
 In order to use the stackdriver console and run the project's tests,
 there is a small amount of setup:
 
-1. Install Ruby. stackdriver requires Ruby 2.4+. You may choose to
+1. Install Ruby. stackdriver requires Ruby 2.5+. You may choose to
    manage your Ruby and gem installations with [RVM](https://rvm.io/),
    [rbenv](https://github.com/rbenv/rbenv), or
    [chruby](https://github.com/postmodern/chruby).
 
 2. Install [Bundler](http://bundler.io/).
@@ -43,10 +43,10 @@
 
 4. Install the Stackdriver dependencies.
 
    ```sh
    $ cd stackdriver/
-   $ bundle exec rake bundleupdate
+   $ bundle install
    ```
 
 ## Stackdriver Tests
 
 Tests are very important part of stackdriver. All contributions