community: Add PolygonLastQuote Tool and Toolkit (#15990)

**Description:** 
In this PR, I am adding a `PolygonLastQuote` Tool, which can be used to
get the latest price quote for a given ticker / stock.

Additionally, I've added a Polygon Toolkit, which we can use to
encapsulate future tools that we build for Polygon.

**Twitter handle:** [@virattt](https://twitter.com/virattt)

---------

Co-authored-by: Harrison Chase <hw.chase.17@gmail.com>

libs/community/langchain_community/agent_toolkits/polygon/toolkit.py

@@ -0,0 +1,27 @@
+from typing import List
+
+from langchain_community.agent_toolkits.base import BaseToolkit
+from langchain_community.tools import BaseTool
+from langchain_community.tools.polygon import PolygonLastQuote
+from langchain_community.utilities.polygon import PolygonAPIWrapper
+
+
+class PolygonToolkit(BaseToolkit):
+    """Polygon Toolkit."""
+
+    tools: List[BaseTool] = []
+
+    @classmethod
+    def from_polygon_api_wrapper(
+        cls, polygon_api_wrapper: PolygonAPIWrapper
+    ) -> "PolygonToolkit":
+        tools = [
+            PolygonLastQuote(
+                api_wrapper=polygon_api_wrapper,
+            )
+        ]
+        return cls(tools=tools)
+
+    def get_tools(self) -> List[BaseTool]:
+        """Get the tools in the toolkit."""
+        return self.tools