DEV: stop leaking data into tables during test (#21403)

This amends it so our cached counting reliant specs run in synchronize mode

When running async there are situations where data is left over in the table
after a transactional test. This means that repeat runs of the test suite
fail.

spec/lib/middleware/request_tracker_spec.rb

@@ -21,6 +21,7 @@ RSpec.describe Middleware::RequestTracker do
   end
 
   after do
+    CachedCounting.reset
     ApplicationRequest.disable
     CachedCounting.disable
   end