Fix broken cell in prompting guide (openai#1842)

Author: imran-binhasan

examples/gpt4-1_prompting_guide.ipynb

@@ -577,11 +577,11 @@
     "Guidance specifically for adding a large number of documents or files to input context:\n",
     "\n",
     "* XML performed well in our long context testing.  \n",
-    "  * Example: `<doc id="1" title="The Fox">The quick brown fox jumps over the lazy dog</doc>`  \n",
+    "  * Example: `<doc id='1' title='The Fox'>The quick brown fox jumps over the lazy dog</doc>`  \n",
     "* This format, proposed by Lee et al. ([ref](https://arxiv.org/pdf/2406.13121)), also performed well in our long context testing.  \n",
     "  * Example: `ID: 1 | TITLE: The Fox | CONTENT: The quick brown fox jumps over the lazy dog`  \n",
     "* JSON performed particularly poorly.  \n",
-    "  * Example: `[{"id": 1, "title": "The Fox", "content": "The quick brown fox jumped over the lazy dog"}]`\n",
+    "  * Example: `[{'id': 1, 'title': 'The Fox', 'content': 'The quick brown fox jumped over the lazy dog'}]`\n",
     "\n",
     "The model is trained to robustly understand structure in a variety of formats. Generally, use your judgement and think about what will provide clear information and “stand out” to the model. For example, if you’re retrieving documents that contain lots of XML, an XML-based delimiter will likely be less effective. \n",
     "\n",