Handle IPv6 localhost URLs in http-server package

[hacksparrow]

Description / Steps to reproduce / Feature proposal

http-server does not format IPv6 address properly in its url property.

Discussion: #1369 (comment)

Current Behavior

Eg: https://:::51492

Expected Behavior

Eg: https://[::]:51492

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[dhmlau]

I assume from the discussion in #1369, we agree to include it in DP3?

[hacksparrow]

Fixed via #1454.