When checking the unit state after `systemctl freeze|thaw` we can be
"too fast" and get the intermediate state (freezing/thawing) which we're
not interested in. Let's wait a bit and try to get the state again in
such cases to avoid unnecessary flakiness.
```
[ 29.390203] testsuite-38.sh[218]: + state=thawing
[ 29.390203] testsuite-38.sh[218]: + '[' thawing = running ']'
[ 29.390203] testsuite-38.sh[218]: + echo 'error: unexpected freezer state, expected: running, actual: thawing'
[ 29.390203] testsuite-38.sh[218]: error: unexpected freezer state, expected: running, actual: thawing
[ 29.390203] testsuite-38.sh[218]: + exit 1
```
Frantisek Sumsal
Zbigniew Jędrzejewski-Szmek
Michal Sekletár