search: wipe reassuring feedback as soon as searching has finished

When there are no help lines, there won't be any call to update the
actual contents of the bottom window, so... do it immediately after
blanking the row.

This fixes https://savannah.gnu.org/bugs/?52377.

src/search.c

@@ -348,6 +348,7 @@ int findnextstr(const char *needle, bool whole_word_only, int modus,
     /* Wipe the "Searching..." message and unset the suppression flag. */
     if (feedback > 0) {
 	blank_statusbar();
+	wrefresh(bottomwin);
 	suppress_cursorpos = FALSE;
     }