[SPARK-15935][PYSPARK] Fix a wrong format tag in the error message

## What changes were proposed in this pull request?

A follow up PR for #13655 to fix a wrong format tag.

## How was this patch tested?

Jenkins unit tests.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #13665 from zsxwing/fix.