Removes 2x requirements file scan
Removes 2x requirements file scan

It was observed that the setup script reads the requirements file twice.
This commit removes a line that may have been left over from a previous
way of defining the project's requirements, and shifts the
responsibility of reading the project's dependencies to the
`pip_requirements` function.

ocefpaf/compliance-checker,ioos/compliance-checker,aodn/compliance-checker