test(sapi): avoid time-based false negatives in test_serialapi

Increase ACK timeout in the test harness so malformed-frame assertions
validate parser behavior instead of failing due to slow tests execution
due because of the host. This is most notably when the test rans in a
Docker container that relies in QEMU to run an armv7 on amd64.

Related-to: ZGW-3458
Origin: SiliconLabs#49
Signed-off-by: Laudin Molina Troconis <laudin.molinatroconis@silabs.com>

Author: lmolina

test/serialapi/test_serialapi.c

@@ -126,7 +126,7 @@ uint8_t Device_SendFrame(session_t *session) {
 
   {
     fd_set rfds;
-    struct timeval tv = {.tv_usec = 100};
+    struct timeval tv = {.tv_usec = 1000};
 
     FD_ZERO(&rfds);
     FD_SET(end_device, &rfds);