## What changes were proposed in this pull request?

fix comparing Vector bug in TestingUtils.
There is the same bug for Matrix comparing. How to check the length of Matrix should be discussed first.

## How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)

(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

Author: Peng, Meng <peng.meng@intel.com>

Closes #14785 from mpjlu/testUtils.