Ignore empty keywords.

Keywords without a label have always been ignored. We need to ignore them when applying the new gene ontology code validator, too.

Author: jstone-dev

src/mavedb/view_models/keyword.py

@@ -31,10 +31,10 @@ def validate_key(cls, v: str) -> str:
 
     @model_validator(mode="after")
     def validate_code(self):
-        keywords.validate_code(self.key, self.label, self.code)
+        if self.label is not None:  # The client may submit empty keywords, which are removed before saving.
+            keywords.validate_code(self.key, self.label, self.code)
         return self
 
-
     # TODO#273: Un-commenting this block will require new experiments to contain a keyword on creation.
     # @field_validator("label")
     # def validate_value(cls, v):