Add .pypirc to the Python.gitignore file

[matheusfelipeog]

.pypirc is a file that stores some information for python package distribution, such as repository URL, username and password.

Definitely this file cannot be uploaded to GitHub, as it contains access credentials for the python packages distribution platform.

See about the .pypirc file at: https://packaging.python.org/en/latest/specifications/pypirc/