[TESTS] add a debug patch to help trigger the stats bug

About: [BUG] Flush buffers also where there are exactly 0 bytes left

I'm also attaching a debug patch that helps to trigger this bug.

Without the fix:
# echo -ne "GET /haproxy?stats;csv;norefresh HTTP/1.0\r\n\r\n"|nc 127.0.0.1
801|wc -c
16384

With the fix:
# echo -ne "GET /haproxy?stats;csv;norefresh HTTP/1.0\r\n\r\n"|nc 127.0.0.1
801|wc -c
33089

Best regards,

                                Krzysztof Oledzki
1 file changed