Fix the issue #117

Simple fix for an existing issue with 'morgan' kind in FPVecTransformer 
#107

molfeat/trans/fp.py

@@ -122,7 +122,7 @@ def _prepare_featurizer(cls, kind: str, length: int, **params):
                 radius = max(radius // 2, 1)
             params["radius"] = radius
         if any(x in kind for x in ["morgan", "morgan_circular", "morgan-circular"]):
-            kind.replace("_circular", "").replace("-circular", "").replace("morgan", "ecfp")
+            kind = kind.replace("_circular", "").replace("-circular", "").replace("morgan", "ecfp")
         if kind not in cls.AVAILABLE_FPS:
             raise ValueError(f"{kind} is not a valid featurizer")
         params["length"] = length