Remove CommandBase check (#60)

Author: spacey-sooty

Diff for: commands2/__init__.py

@@ -85,10 +85,4 @@ def __getattr__(attr):
             )
             return Subsystem
 
-        if attr == "CommandBase":
-            import warnings
-
-            warnings.warn("CommandBase is deprecated", DeprecationWarning, stacklevel=2)
-            return Command
-
         raise AttributeError(f"module {__name__!r} has no attribute {attr!r}")