[skip ci] prevent blank names on filter spectrum name

Author: tlambert03

proteins/models/spectrum.py

@@ -419,7 +419,7 @@ def name(self):
         elif self.owner_dye:
             return "{} {}".format(self.owner, self.subtype)
         elif self.owner_filter:
-            return "{}".format(self.owner.part)
+            return str(self.owner.part or self.owner)
         else:
             return str(self.owner)