FIX: don't run_test in testing env

Author: keegangeorge

lib/configuration/simple_llm_validator.rb

@@ -18,6 +18,11 @@ def valid_value?(val)
       end
 
       def run_test(val)
+        if Rails.env.test?
+          # In test mode, we assume the model is reachable.
+          return true
+        end
+
         DiscourseAi::Completions::Llm
           .proxy(val)
           .generate("How much is 1 + 1?", user: nil, feature_name: "llm_validator")