fix: model.BomMetaData.component setter typehint

Signed-off-by: Jan Kowalleck <jan.kowalleck@gmail.com>

Author: jkowalleck

cyclonedx/model/bom.py

@@ -179,7 +179,7 @@ def component(self) -> Optional[Component]:
         return self._component
 
     @component.setter
-    def component(self, component: Component) -> None:
+    def component(self, component: Optional[Component]) -> None:
         """
         The (optional) component that the BOM describes.