Fix: Statistic datasets try to write attributes despite not writing the dataset

Issue

When we create Value objects without a function to write datasets, we still try to write the attributes on the dataset. This always fails because the dataset write was skipped. We should not try to write the attributes if the dataset is not meant to be written.

Bug probably introduced here: !692 (merged)

Description of work

Condition attribute write to dataset being written in the first place

Checklist

• Changes have been documented in changes.md
• Documentation has been updated in documentation directory