text: Title: [Ray Core] `ray.data.Dataset.repartition` not working consistently with doc/error message
  Body: ### What happened + What you expected to happen
  
  ```
  ds = ds.repartition(num_blocks=x, target_num_rows_per_block=y)
  ```
  Obviously it's conflicting to setting both. Calling this gives the error `ValueError: Either num_blocks or target_num_rows_per_block must be set, but not both.`, as expected.
  
  But this doesn't work `ds = ds.repartition(target_num_rows_per_block=y)`. I got `TypeError: Dataset.repartition() missing 1 required positional argument: 'num_blocks'`
  
  
  This doesn't seem to make sense to me. According to [doc](https://docs.ray.io/en/latest/data/api/doc/ray.data.Dataset.repartition.html), it should be happy with one of the 2 arguments given. 
  
  
  ### Versions / Dependencies
  
  ray 2.43.0
  Python 3.11.11
  Ubuntu 22.04.3 LTS
  
  ### Reproduction script
  
  ```
  import ray
  ds = ray.data.range(100)
  ds.repartition(target_num_rows_per_block=10)
  ```
  
  ### Issue Severity
  
  None