patch 8.2.0884: searchcount() test fails on slower systems

Problem:    Searchcount() test fails on slower systems.
Solution:   Set a longer timeout.
diff --git a/src/search.c b/src/search.c
index a6b60f6..0c253e9 100644
--- a/src/search.c
+++ b/src/search.c
@@ -36,7 +36,7 @@
 static void cmdline_search_stat(int dirc, pos_T *pos, pos_T *cursor_pos, int show_top_bot_msg, char_u *msgbuf, int recompute, int maxcount, long timeout);
 static void update_search_stat(int dirc, pos_T *pos, pos_T *cursor_pos, searchstat_T *stat, int recompute, int maxcount, long timeout);
 
-#define SEARCH_STAT_DEF_TIMEOUT 20L
+#define SEARCH_STAT_DEF_TIMEOUT 40L
 #define SEARCH_STAT_DEF_MAX_COUNT 99
 #define SEARCH_STAT_BUF_LEN 12