Force SSL when RAILS_ENV=production

This ensures that we don't get warnings about SameSite=None cookies
as a result of 8785e73. The warnings indicate that at some point the
browser will no longer honor these cookies unless they are sent
securely.

config/environments/production.rb

@@ -48,7 +48,7 @@
   # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
 
   # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
-  # config.force_ssl = true
+  config.force_ssl = true
 
   # Include generic and useful information about system operation, but avoid logging too much
   # information to avoid inadvertent exposure of personally identifiable information (PII).