Fix typo in py-propka/package.py

packages/py-propka/package.py

@@ -8,7 +8,7 @@
 from spack import *
 
 
-class Propka(PythonPackage):
+class PyPropka(PythonPackage):
     """
     PROPKA predicts the pKa values of ionizable
     groups in proteins (version 3.0) and protein-ligand