"deserialize" from base class Model should have types

[lmazuel]

msrest-for-python/msrest/serialization.py

Line 319 in 98e2ebe

def deserialize(cls, data, content_type=None):

To avoid:
https://github.com/Azure/azure-sdk-for-python/pull/14344/files#r501379989

[lmazuel]

Probably something like:

(Type[T], Any, Optional[str]) -> T