Use async clipboard api [1] over this dependency, saving around 10kB
bundle size before minify while delivering the same functionality.
The issue comment button works but does not have a popup indication. We
could add some toast-style notifications in the future to fix that but I
think it's out of scope of this PR.
[1] https://developer.mozilla.org/en-US/docs/Web/API/Clipboard/writeText
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