CI failed due to new numpy release - 1.20

[anmyachev]

System information

• OS Platform and Distribution (e.g., Linux Ubuntu 16.04):
• Modin version (modin.__version__): 03ea9b2
• Python version: 3.8.6
• Code we can use to reproduce: python -m pytest --simulate-cloud=normal modin/pandas/test/test_io.py::TestCsv

Describe the problem

We use assert_frame_equal from pandas to check equality of dataframes. It seems that pandas doesn't support changes in numpy classes from 1.20 release.

Source code / logs