Add feature flag around tallying to make it unreachable in production

Author: jhenderson

app/helpers/application_helper.rb

@@ -61,6 +61,6 @@ def opengraph_image_tag(service_url, name)
   def cached_counts = TeamCachedCounts.new(current_team)
 
   def tallying_enabled?
-    params[:tallies] == "true"
+    Flipper.enabled?(:tallying) && params[:tallying] == "true"
   end
 end

config/feature_flags.yml

@@ -19,8 +19,10 @@ import_low_pds_match_rate: Prevent processing uploads with a low pds match rate.
 pds_lookup_during_import: Perform PDS lookups as part of the patient import
   processing.
 
+tallying: Enables the session tally-based overview page
+
 testing_api: Basic API useful for automated testing.
 
 reporting_api: Enables the Commissioner reporting component to authenticate to Mavis via OAUTH 2.0
   Authorization Code Flow (https://datatracker.ietf.org/doc/html/rfc6749#section-4.1), and retrieve
-  statistics from /api/reporting/
+  statistics from /api/reporting/