Fix broken openai import in Azure_OpenAI_Graders notebook (#291)

* Initial plan

* Fix outdated openai import in Azure_OpenAI_Graders notebook

Co-authored-by: w-javed <7674577+w-javed@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: w-javed <7674577+w-javed@users.noreply.github.com>

Author: Copilot

scenarios/evaluate/Azure_OpenAI_Graders/Azure_OpenAI_Graders.ipynb

@@ -64,7 +64,7 @@
     "    AzureOpenAIGrader,\n",
     "    evaluate,\n",
     ")\n",
-    "from openai.types.eval_string_check_grader import EvalStringCheckGrader"
+    "from openai.types.graders.string_check_grader import StringCheckGrader"
    ]
   },
   {
@@ -235,7 +235,7 @@
    "outputs": [],
    "source": [
     "# Define an string check grader config directly using the OAI SDK\n",
-    "oai_string_check_grader = EvalStringCheckGrader(\n",
+    "oai_string_check_grader = StringCheckGrader(\n",
     "    input=\"{{item.query}}\", name=\"contains hello\", operation=\"like\", reference=\"hello\", type=\"string_check\"\n",
     ")\n",
     "# Plug that into the general grader\n",