fix: skip evaluation if no evaluator model is specified in verify_solution

aider_gitea/__init__.py

@@ -387,6 +387,9 @@ def run_ollama_and_get_yes_or_no(cwd, initial_texts: list[str]) -> bool:
 
 
 def verify_solution(repository_path: Path, issue_content: str) -> bool:
+    if not EVALUATOR_MODEL:
+        return True
+
     summary = run_ollama(
         repository_path,
         [