Fix: Replaced 'py' with 'python' in chocolatey install script

[VeronicaOcampo]

This pull request fixes issue #1617 by replacing the use of 'py' with 'python' to ensure better compatibility on systems where 'py' is not recognized (like windows). The changes can be seen in the chocolateyinstall.ps1 and the chocolateyuninstall.ps1