Update README.rst

Author: alexanderdean

README.rst

@@ -47,7 +47,8 @@ Contributing quickstart
   $ git clone --recursive https://github.com/snowplow/dev-environment.git
   $ cd dev-environment
   $ ansible-playbook /vagrant/ansible-playbooks/snowplow-python-tracker.yml --inventory-file=/home/vagrant/ansible_hosts --connection=local
-  $ ...
+  $ cd /vagrant/snowplow-python-tracker
+  $ ./runtests.sh
 
 Copyright and license
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