Bug/pdf grover

[briri]

Fixes #604.

Changes proposed in this PR:

• Replace use of wicked_pdf gem which used the now defunct wkhtmltopdf package with the grover gem which uses puppeteer and headless chrome. This occurs in the following files: plan_exports_controller.rb, pdf_publisher_job.rb and public_pages_controller
• Updated Gemfile to remove the aforementioned gems and add grover
• Removed wkhtmltopdf from Rails config
• Added an initializer to setup grover properly
• Add the publisher_job_status field to the templates table and added narrative to the template model so that we can store the PDF version of a template in ActiveStorage
• Update the Template publication workflow so that it pre-renders the template as a PDF and stores it in ActiveStorage
• Update both the public facing "Funder Requirements" and "Public Plans" pages to return the pre-rendered PDFs from ActiveStorage when available.
• Update the PdfPublisherJob to use Grover to build PDFs
• Added Roboto and Tinos fonts
• Added new tasks for Capistrano so that it will install Chrome on the server if it does not already exist and will also install the Roboto and Tinos fonts
• Added Rake task to pre-render all public templates
• Updated gem and JS dependencies