Automatic generation of release notes (#35977)

Similar to GitHub, release notes can now be generated automatically.
The generator is server-side and gathers the merged PRs and contributors
and returns the corresponding Markdown text.

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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

web_src/js/features/comp/ComboMarkdownEditor.ts

@@ -410,7 +410,7 @@ export class ComboMarkdownEditor {
   }
 }
 
-export function getComboMarkdownEditor(el: any) {
+export function getComboMarkdownEditor(el: any): ComboMarkdownEditor | null {
   if (!el) return null;
   if (el.length) el = el[0];
   return el._giteaComboMarkdownEditor;