patch 8.1.2313: debugging where a delay comes from is not easy

Problem:    Debugging where a delay comes from is not easy.
Solution:   Use different values when calling ui_delay().
diff --git a/src/search.c b/src/search.c
index 00f0a08..cff289c 100644
--- a/src/search.c
+++ b/src/search.c
@@ -2726,9 +2726,9 @@
 	     * available.
 	     */
 	    if (vim_strchr(p_cpo, CPO_SHOWMATCH) != NULL)
-		ui_delay(p_mat * 100L, TRUE);
+		ui_delay(p_mat * 100L + 8, TRUE);
 	    else if (!char_avail())
-		ui_delay(p_mat * 100L, FALSE);
+		ui_delay(p_mat * 100L + 9, FALSE);
 	    curwin->w_cursor = save_cursor;	/* restore cursor position */
 	    *so = save_so;
 	    *siso = save_siso;