Add custom hotkeys. (#2340)

Co-authored-by: LosFarmosCTL <80157503+LosFarmosCTL@users.noreply.github.com>
Co-authored-by: Paweł <zneix@zneix.eu>
Co-authored-by: Felanbird <41973452+Felanbird@users.noreply.github.com>
Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/widgets/dialogs/SelectChannelDialog.hpp

@@ -64,6 +64,8 @@ private:
 
     void ok();
     friend class EventFilter;
+
+    void addShortcuts() override;
 };
 
 }  // namespace chatterino