user-accounts: Fix libpwquality error handling

Always use pwquality_strerror()	in case	of error in order to prevent
memory leaks and to improve error messages.

#171
11 jobs for wip/oholy/libpwquality-crashes in 9 minutes and 7 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #101388
build

00:06:40

 
  Test
passed #101390
asan

00:02:26

passed #101389
test

00:00:37

 
  Manual
manual #101395
allowed to fail manual
armv8
manual #101391
allowed to fail manual
flatpak
manual #101394
allowed to fail manual
msan
manual #101396
allowed to fail manual
ppc64le
manual #101392
allowed to fail manual
tsan
manual #101393
allowed to fail manual
ubsan
 
  Review
manual #101397
allowed to fail manual
review
manual #101398
allowed to fail manual
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