Fix memory leaks detected by running tests with AddressSanitizer

[maciej-pawlowski-opera]

Two memory leaks were found when running tests built with asan.

[abby-sergz]

Hello @maciej-pawlowski-opera,

Thanks a lot for the contribution. We will process it, however we are currently restructuring our internal processes and therefore our reaction can be way too slow, despite the change might look pretty straightforward. I hope on your understanding.

FYI, this github repository is basically a mirror of https://gitlab.com/eyeo/adblockplus/libadblockplus, where the main development is happening. So, the pull request (merge request) should be rather sent onto the gitlab repository. However I would recommend to wait for a confirmation from eyeo GmbH beforehand.

[maciej-pawlowski-opera]

Sure thing, I'll recreate this fix on gitlab when I have a minute and I'll let you figure out how to process it whenever you see fit.