Use translated docs in PropertySelector

And do the dedent and stripping for both translated and
non-translated strings for consistency, and so that we
don't need to do it at the call site.

(cherry picked from commit a16031beb6)

editor/connections_dialog.cpp

@@ -1001,7 +1001,7 @@ void ConnectionsDock::update_tree() {
 					while (F && descr == String()) {
 						for (int i = 0; i < F->get().signals.size(); i++) {
 							if (F->get().signals[i].name == signal_name.operator String()) {
-								descr = DTR(F->get().signals[i].description.strip_edges());
+								descr = DTR(F->get().signals[i].description);
 								break;
 							}
 						}