Make search results font follow code editor font

The font size of the Find in Files dialog used to get out of sync with
the code editor font size.

The font of the Find in Files dialog is now updated each time there is a
change to the theme. This way, the font size of the Find in Files
results changes in response to the code font size being changed using
Ctrl +/- or using the Editor Settings.

Fixes #35499

(cherry picked from commit 011fdece6d5a6570512b5b6fd112183363c7c318)

editor/find_in_files.cpp

@@ -640,6 +640,9 @@ void FindInFilesPanel::stop_search() {
 void FindInFilesPanel::_notification(int p_what) {
 	if (p_what == NOTIFICATION_PROCESS) {
 		_progress_bar->set_as_ratio(_finder->get_progress());
+	} else if (p_what == NOTIFICATION_THEME_CHANGED) {
+		_search_text_label->add_font_override("font", get_font("source", "EditorFonts"));
+		_results_display->add_font_override("font", get_font("source", "EditorFonts"));
 	}
 }