Match requests by body

So that modifying the prompt make the tests fail

If not, the tests defeat their purpose!

test/test_helper.rb

@@ -11,6 +11,9 @@ VCR.configure do |config|
   config.cassette_library_dir = "test/vcr_cassettes"
   config.hook_into :webmock
   config.filter_sensitive_data("<OPEN_API_KEY>") { Rails.application.credentials.openai_api_key || ENV["OPEN_AI_API_KEY"] }
+  config.default_cassette_options = {
+    match_requests_on: [:method, :uri, :body]
+  }
 end
 
 module ActiveSupport