[SPARK-20854][TESTS] Removing duplicate test case

## What changes were proposed in this pull request?

Removed a duplicate case in "SPARK-20854: select hint syntax with expressions"

## How was this patch tested?
Existing tests.

Author: Bogdan Raducanu <bogdan@databricks.com>

Closes #18217 from bogdanrdc/SPARK-20854-2.