[PR-comment] support comment links

[akosyakov]

One should be able click on a date to copy a link to a comment.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[akosyakov]

We are switching to VS Code and https://www.gitpod.io/docs/feature-preview/#default-ide for PR reviews on gitpod.io In order to enable VS Code follow https://github.com/microsoft/vscode-pull-request-github