fix:urge customers to install latest version (#4507)

Author: akrishna1995

README.rst

@@ -67,11 +67,10 @@ Table of Contents
 Installing the SageMaker Python SDK
 -----------------------------------
 
-The SageMaker Python SDK is built to PyPI and can be installed with pip as follows:
-
+The SageMaker Python SDK is built to PyPI and the latest version of the SageMaker Python SDK can be installed with pip as follows
 ::
 
-    pip install sagemaker
+    pip install sagemaker==<Latest version from pyPI from https://pypi.org/project/sagemaker/>
 
 You can install from source by cloning this repository and running a pip install command in the root directory of the repository: