PublicLab: Mapknitter Export Module and Spectral Workbench upgrades

For the Spectral Workbench project, Rails and DevOps improvements that will involve upgrading from Rails 3.2 to Rails 6.0, properly setting up continuous integration and delivery, removal of deprecated modules and tools, increase test coverage, setup of monitoring tools, configuring containerized environments and much more. For Mapknitter export module, involves running the exporting process as a scalable web service - which has been recently achieved; but also work on the performance of the Export module, by doing some refactoring and including previously defined feature with it.