Remove now unused mock and vagrant infra #84

In the early development of this framework, tests ran against python-based mocks using https://github.com/DMTF/Redfish-Mockup-Server and https://github.com/dell/iDRAC-Redfish-Scripting . It has since moved on to using https://github.com/simontesar/metal-lab for development.
The vagrant-based setup here was also primarily used to develop/showcase a physical setup and its architecture has been integrated into the metal-lab as well.

• Remove mock-based infra
• Remove vagrant-based infra