`Install-WinCNIPlugin` should also setup the configs

[profnandaa]

Describe the bug

Currently Install-WinCNIPlugin only downloads the binaries and puts them in `Containerd\cni\bin'. I think the user expects that this will also set up the required configs and wire everything up so that at the end container networking is up and running.

Perhaps even doing a dial test at the end of the installation will be ideal:

# can detect which YEAR to pick from the window version information
# WS2025 can run both ltsc2025 and ltsc2022
ctr image pull mcr.microsoft.com/windows/nanoserver:ltsc<YEAR>
ctr run --rm mcr.microsoft.com/windows/nanoserver:ltsc<YEAR> cni-test cmd /C ping bing.com