Use test

Signed-off-by: Ethan Dye <[email protected]>

tests/run.exp

@@ -75,7 +75,7 @@ expect {
   }
 }
 expect "pi@raspberrypi:~$ "
-send "if ! [[ -f /var/log/test.txt ]]; then echo Failed; fi\r"
+send "test -f /var/log/test.txt || echo Failed\r"
 expect {
   "Failed" {
     set retval 1