Set sanitizer options directly

[lzaoral]

util-linux has the following line in its test-suite:

https://github.com/util-linux/util-linux/blob/90b12595bbe3357fdbccf5eec6c3885e53bc614e/tests/functions.sh#L302

Thus, it will override any setting (e.g. log collection) csmock has set. We can use csexec to make sure the environment will be set correctly.

[kdudka]

Sounds like a good idea. We will still have a problem if someone executes the test-suite in a sanitized environment (obtained e.g. by env -i ...) because it will wipe our configuration for csexec.