Configure GitHub Actions with WSL to properly test WSL support

[kapoorlakshya]

Configure GitHub Actions with WSL to properly test WSL support.

References:

• https://github.com/marketplace/actions/setup-wsl

• Only WSL v1 is available in Win 2k19 image - https://github.com/actions/virtual-environments/blob/main/images/win/Windows2019-Readme.md