HexEditor: Change `Find All Strings` shortcut to `Ctrl + Shift + F`

The previous shortcut of `Ctrl + Shift + S` conflicted with `Save As...`
action shortcut.

Userland/Applications/HexEditor/HexEditorWidget.cpp

@@ -401,7 +401,7 @@ void HexEditorWidget::initialize_menubar(GUI::Window& window)
         m_last_found_index = result.value();
     }));
 
-    edit_menu.add_action(GUI::Action::create("Find All &Strings", { Mod_Ctrl | Mod_Shift, Key_S }, Gfx::Bitmap::try_load_from_file("/res/icons/16x16/find.png"sv).release_value_but_fixme_should_propagate_errors(), [&](const GUI::Action&) {
+    edit_menu.add_action(GUI::Action::create("Find All &Strings", { Mod_Ctrl | Mod_Shift, Key_F }, Gfx::Bitmap::try_load_from_file("/res/icons/16x16/find.png"sv).release_value_but_fixme_should_propagate_errors(), [&](const GUI::Action&) {
         int min_length = 4;
         auto matches = m_editor->find_all_strings(min_length);
         m_search_results->set_model(*new SearchResultsModel(move(matches)));