tests: runtime: in_tail: remove unused var

Signed-off-by: Takahiro Yamashita <[email protected]>

Author: nokute78

tests/runtime/in_tail.c

@@ -287,7 +287,6 @@ void wait_with_timeout(uint32_t timeout_ms, struct tail_test_result *result, int
     struct flb_time end_time;
     struct flb_time diff_time;
     uint64_t elapsed_time_flb = 0;
-    int64_t ret = 0;
 
     flb_time_get(&start_time);