remove used_in_reference in ElectrodeConfig

this is misleading as it's only relevant for SpikeGLX acquisition for denoting channel visualization

Author: Thinh Nguyen

elements_ephys/ephys.py

@@ -159,7 +159,7 @@ def make(self, key):
                         electrode = (q_electrodes & {'shank': shank,
                                                      'shank_col': shank_col,
                                                      'shank_row': shank_row}).fetch1('KEY')
-                        eg_members.append({**electrode, 'used_in_reference': is_used})
+                        eg_members.append(electrode)
                 else:
                     raise NotImplementedError('Processing for neuropixels probe model {} not yet implemented'.format(
                         spikeglx_meta.probe_model))

elements_ephys/probe.py

@@ -144,6 +144,4 @@ class Electrode(dj.Part):
         definition = """  # Electrodes selected for recording
         -> master
         -> ProbeType.Electrode
-        ---
-        used_in_reference=null: bool  # is this channel used to form the internal reference
         """