chunk_trace: add wait in test to avoid use after free in lib callback.

Signed-off-by: Phillip Whelan <[email protected]>

tests/runtime/core_chunk_trace.c

@@ -107,6 +107,7 @@ void do_test_records_trace(void (*records_cb)(struct callback_records *))
     records_cb(records);
 
     flb_stop(ctx);
+    sleep(5);
 
     for (i = 0; i < records->num_records; i++) {
         flb_lib_free(records->records[i].data);