message: docs: add contribute content section
diff: @@ -116,6 +116,7 @@ export const MENU: MenuEntry[] = [
  M("Gitpod Releases", "references/gitpod-releases"),
  ]),
  M("Contribute", "contribute", [
  + M("Content", "contribute/content"),
  M("Documentation", "contribute/documentation"),
  M("Features & Patches", "contribute/features-and-patches"),
  ]),
  