### What changes were proposed in this pull request?
This patch adds a benchmark `SubExprEliminationBenchmark` for benchmarking subexpression elimination feature.
### Why are the changes needed?
We need a benchmark for subexpression elimination feature for change such as #30341.
### Does this PR introduce _any_ user-facing change?
No, dev only.
### How was this patch tested?
Unit test.
Closes#30379 from viirya/SPARK-33455.
Authored-by: Liang-Chi Hsieh <viirya@gmail.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
