[CI] Fail on WIN random: OmSessionStoreTest(OmStoreTest)>>testEntryForAbsentEntry

**Bug description**
OmSessionStoreTest(OmStoreTest)>>testEntryForAbsentEntry fails on the CI on Windows only randomly

```

FileDoesNotExistException
'C:\Users\ci\AppData\Local\Temp\ombu-tests\test-sessions-other\Pharo.38D0549E180.ombu'
```