relates to https://github.com/coder/internal/issues/912
Adds a new scaletest Runner to generate dynamic parameters load.
A later PR will add the CLI command, including creating the template & version.
This PR extracts dynamic parameter rendering logic from
coderd/parameters.go into a new coderd/dynamicparameters package. Partly
for organization and maintainability, but primarily to be reused in
`wsbuilder` to be leveraged as validation.
Spike Curtis