fix

Signed-off-by: BubbleCal <bubble-cal@outlook.com>

Author: BubbleCal

rust/lance/src/index/vector/builder.rs

@@ -472,10 +472,6 @@ impl<S: IvfSubIndex + 'static, Q: Quantization + 'static> IvfIndexBuilder<S, Q>
 
     #[instrument(name = "build_partitions", level = "debug", skip_all)]
     async fn build_partitions(&mut self) -> Result<&mut Self> {
-        let dataset = self.dataset.as_ref().ok_or(Error::invalid_input(
-            "dataset not set before building partitions",
-            location!(),
-        ))?;
         let ivf = self.ivf.as_mut().ok_or(Error::invalid_input(
             "IVF not set before building partitions",
             location!(),