* fix: coverity regressions reported on 2021-10-01
leaks introduced by 3fd5c81a
* fix: resource leak in test utility filesAreIdentical()
* fix: use-after-free warning in test code for tr_urlParse()
* fix: false warning for unterminated c string
* fix: false unchecked return value in test code
cid 1491881
* fix: unterminated c string in test code
cid 1491890
* refactor: slightly better assertions in file-test
* refactor: keep torrent hash in std::array<char,20>
This replaces the hashString QString allocation with a compile-time
array that's included in sizeof the Torrent struct that owns it.
