Update dummy_agent_library.ipynb

corrected typo on line 237: change 'have' for 'has' for grammatical correctness.

dummy_agent_library.ipynb

@@ -234,7 +234,7 @@
    "outputs": [],
    "source": [
     "# This system prompt is a bit more complex and actually contains the function description already appended.\n",
-    "# Here we suppose that the textual description of the tools have already been appended\n",
+    "# Here we suppose that the textual description of the tools has already been appended\n",
     "SYSTEM_PROMPT = \"\"\"Answer the following questions as best you can. You have access to the following tools:\n",
     "\n",
     "get_weather: Get the current weather in a given location\n",