`Cancel` button when editing wiki pages #4460

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When editing a page on a GitHub wiki, there is no intuitive way to stop editing and discarding the changes. Unlike editing e.g. issue titles or issue text. (Note that the first shows a link, the second has a red-label button)

The only cancel-ish thing users see is a red-label Delete button which could easily be confused with the same looking Cancel button known from issues already: (To remove the danger here, the delete one could have a trash can icon as well.)