Docs: Change formatting for sequence of steps

A numbered list is used when the sequence of steps matters. A bulleted list is used to denote a set of items where the sequence does not matter.

The workflow is a sequence and hence changed to a numbered list.

Author: vivganes

CONTRIBUTING.md

@@ -24,9 +24,9 @@ facilitates social contribution, easy testing and peer review.
 
 To contribute a patch, the workflow is as follows:
 
-  - Fork repository
-  - Create topic branch
-  - Commit patches
+  1. Fork repository
+  1. Create topic branch
+  1. Commit patches
 
 The project coding conventions in the [developer notes](doc/developer-notes.md)
 must be adhered to.