Apply suggestion from @dusanparipovic

Author: dusanparipovic

src/gems/model/parsing.py

@@ -87,7 +87,7 @@ class ExtraOutputSchema(ModifiedBaseModel):
 
 class ModelSchema(ModifiedBaseModel):
     id: str
-    taxonomy_category: Optional[str] = None  # # Optional or mandatory,open question ?
+    taxonomy_category: Optional[str] = None 
     parameters: List[ParameterSchema] = Field(default_factory=list)
     variables: List[VariableSchema] = Field(default_factory=list)
     ports: List[ModelPortSchema] = Field(default_factory=list)