DOC: Removed link to Engarde project. It doesn't develop anymore. #44543
issues #44543 

Removed link to [Engarde](https://engarde.readthedocs.io/en/latest/) project. It doesn't develop anymore [GitHab](https://github.com/engarde-dev/engarde#readme).

Added a link to the actively developing project  [Pandera](https://pandera.readthedocs.io/en/stable/) [GitHab](https://github.com/pandera-dev/pandera).




thanks @Mikhaylov-yv 