Fix memory leak in lex_test.c

(cherry picked from commit 7a3eb391)
19 jobs for 711-fix-memory-leak-in-lex_test-v9_12 in 13 minutes and 46 seconds (queued for 25 seconds)
Status Job ID Name Coverage
  Precheck
passed precheck:debian:sid:amd64 #101535
amd64 docker linux

00:00:23

 
  Build
passed build:centos:centos6:amd64 #101536
amd64 docker linux

00:03:18

passed build:centos:centos7:amd64 #101537
amd64 docker linux

00:03:17

passed build:debian:sid:amd64 #101538
amd64 docker linux

00:02:27

passed build:debian:sid:i386 #101539
i386 docker linux

00:02:03

passed noassert:build:debian:sid:amd64 #101540
amd64 docker linux

00:01:56

 
  Test
passed docs:debian:sid:amd64 #101541
amd64 docker linux

00:00:53

passed install:debian:sid:amd64 #101550
amd64 docker linux

00:01:43

passed noassert:systemtest:debian:sid:amd64 #101552
amd64 docker linux

00:04:52

passed noassert:unittest:debian:sid:amd64 #101551
amd64 docker linux

00:00:46

passed systemtest:centos:centos6:amd64 #101644
linux docker amd64

00:04:53

passed systemtest:centos:centos7:amd64 #101547
amd64 docker linux

00:04:52

passed systemtest:debian:sid:amd64 #101548
amd64 docker linux

00:04:54

passed systemtest:debian:sid:i386 #101549
i386 docker linux

00:04:53

passed unittest:centos:centos6:amd64 #101542
amd64 docker linux

00:00:53

passed unittest:centos:centos7:amd64 #101543
amd64 docker linux

00:00:54

passed unittest:debian:sid:amd64 #101544
amd64 docker linux

00:00:47

passed unittest:debian:sid:i386 #101545
i386 docker linux

00:00:51

failed systemtest:centos:centos6:amd64 #101546
amd64 docker linux

00:05:15