Validate the construction of `FileScanTaskDeleteFile`.

[CTTY]

We should validate this when building FileScanTaskDeleteFile.

isDv == FileScanTaskDeleteFile.content_type == PosDel && FileScanTaskDeleteFile.file_format == puffin
fn build() {
 if (isDv) { validate_deletion_vector_task() }
}

Originally posted by @CTTY in #3035 (comment)

[CTTY]

We should also address this: #3035 (comment)