Replace apivore with rswag for api tests (#969)

* Replace apivore api tests with rswag
* move to OpenAPI Spec 3.0.1
* a swagger UI is now reachable at http://localhost:3000/api-docs/index.html
*  swagger file is generated by running  `RAILS_ENV=test rails rswag`
    and it was moved from /docs/swagger.v1.yml to /swagger/v1/swagger.yml

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Co-authored-by: viehlieb <pf@pragma-shift.net>

config/initializers/rswag_api.rb

@@ -0,0 +1,13 @@
+Rswag::Api.configure do |c|
+  # Specify a root folder where Swagger JSON files are located
+  # This is used by the Swagger middleware to serve requests for API descriptions
+  # NOTE: If you're using rswag-specs to generate Swagger, you'll need to ensure
+  # that it's configured to generate files in the same folder
+  c.swagger_root = Rails.root.to_s + '/swagger'
+
+  # Inject a lambda function to alter the returned Swagger prior to serialization
+  # The function will have access to the rack env for the current request
+  # For example, you could leverage this to dynamically assign the "host" property
+  #
+  # c.swagger_filter = lambda { |swagger, env| swagger['host'] = env['HTTP_HOST'] }
+end

config/initializers/rswag_ui.rb

@@ -0,0 +1,15 @@
+Rswag::Ui.configure do |c|
+  # List the Swagger endpoints that you want to be documented through the
+  # swagger-ui. The first parameter is the path (absolute or relative to the UI
+  # host) to the corresponding endpoint and the second is a title that will be
+  # displayed in the document selector.
+  # NOTE: If you're using rspec-api to expose Swagger files
+  # (under swagger_root) as JSON or YAML endpoints, then the list below should
+  # correspond to the relative paths for those endpoints.
+
+  c.swagger_endpoint '/api-docs/v1/swagger.yaml', 'API V1 Docs'
+
+  # Add Basic Auth in case your API is private
+  # c.basic_auth_enabled = true
+  # c.basic_auth_credentials 'username', 'password'
+end