[Improvement] Daily performance test concurrency value is reduced to 20. (the original concurrency value is 100)

### What would you like to be improved?

1. The gravitino CPU utilization is up to 98% when run the 100 concurrency. This cause error if not extend the environment resources.

After I reduced to 20 , No error. Try reduced to 30, no effect.

### How should we improve?

The gravitino CPU utilization keep increasing. Figure out the solution that improve the performance.

No file, test path, or entry point is named. Locate the daily performance test, compare concurrency values of 100, 30, and 20 while monitoring Gravitino CPU utilization, and establish a documented solution that avoids errors without simply reducing concurrency.

Written by the indexing model from the issue text.