Coerce type of channels to float

(cherry picked from commit 5a6a2517b452a88e811f43c2daa0d111ac2c592b)

Author: domfournier

simpeg_drivers/components/factories/directives_factory.py

@@ -489,7 +489,7 @@ def assemble_keyword_arguments(
         name=None,
     ):
         receivers = inversion_object.entity
-        channels = getattr(receivers, "channels", [None])
+        channels = [float(val) for val in getattr(receivers, "channels", [None]) if val]
         components = list(inversion_object.observed)
         ordering = inversion_object.survey.ordering
         n_locations = len(np.unique(ordering[:, 2]))