Replace deprecated assertDictContainsSubset

The method is deprecated since Python 3.2[1] and shows the following
DeprecationWarning.

/usr/lib/python3.9/unittest/case.py:1134: DeprecationWarning:
assertDictContainsSubset is deprecated
  warnings.warn('assertDictContainsSubset is deprecated',

[1] https://docs.python.org/3/whatsnew/3.2.html#unittest

Closes-Bug: #1938103
Change-Id: I2e868d13d52a2d3c6081a8b756fbe83f8b57cf66
4 files changed