PR Summary

Update the map between console color to VT sequences.
The ConsoleColor to VT Escape Sequences mapping in VTUtils.cs is not accurate, and thus is updated according to https://docs.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences#text-formatting

The update is needed as "Bright foreground color" (e.g. bright red \x1b[91m) is rendered differently from bold color (e.g. \x1b[1;31m) in some front-end client, such as the Jupyter Notebook client.
See the 3rd and 4th output below as an example:

PR Checklist

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