Make authority exception more informative.

Co-Authored-By: Joris Van den Bossche <jorisvandenbossche@gmail.com>

pyproj/_crs.pyx

@@ -470,7 +470,7 @@ cdef class Ellipsoid(Base):
             PJ_CATEGORY_ELLIPSOID,
         )
         if ellipsoid_pj == NULL:
-            raise CRSError("Invalid authority")
+            raise CRSError("Invalid authority or code ({0}, {1})".format(auth_name, code))
         return Ellipsoid.create(ellipsoid_pj)
 
     @staticmethod