Add action-used-by-link feature (#3033)

Author: maelle

source/index.ts

@@ -407,3 +407,10 @@ export const hasCode = (): boolean => // Static code, not the editor
 	isGist() ||
 	isCompare() ||
 	isBlame();
+
+export const isActionPage = (): boolean => location.pathname.startsWith('/marketplace/actions/');
+export const _isActionPage = [
+	'https://github.com/marketplace/actions/urlchecker-action',
+	'https://github.com/marketplace/actions/github-action-for-assignee-to-reviewer',
+	'https://github.com/marketplace/actions/hugo-actions'
+];