docs: add install in main docs website

Signed-off-by: heitorlessa <lessa@amazon.co.uk>

Author: heitorlessa

docs/content/index.mdx

@@ -5,6 +5,13 @@ description: AWS Lambda Powertools Python
 
 Powertools is a suite of utilities for AWS Lambda Functions that makes tracing with AWS X-Ray, structured logging and creating custom metrics asynchronously easier.
 
+## Install
+
+Powertools is available in PyPi. You can use your favourite dependency management tool to install it
+
+* [poetry](https://python-poetry.org/): `poetry add aws-lambda-powertools`
+* [pip](https://pip.pypa.io/en/latest/index.html): `pip install aws-lambda-powertools`
+
 ## Features
 
 * [Tracing](./core/tracer) - Decorators and utilities to trace Lambda function handlers, and both synchronous and asynchronous functions