Update contribute.ngdoc

Closes #12875

Author: sibStephen

docs/content/misc/contribute.ngdoc

@@ -52,10 +52,12 @@ To build AngularJS, you clone the source code repository and use Grunt to genera
 minified AngularJS files:
 
 ```shell
-# Clone your Github repository(Note: Do not go with `sudo` user when cloning into this repository 
-if not known what it does essentially, please refer https://www.linux.com/learn/tutorials/306766:linux-101-introduction-to-sudo):
+# Clone your Github repository:
 git clone "git@github.com:<github username>/angular.js.git"
 
+**Note:** You may need to use sudo (for OSX, *nix, BSD etc) or run your command shell as Administrator (for Windows) to install Grunt &amp;
+Bower globally.
+
 # Go to the AngularJS directory:
 cd angular.js