Run static fuzzing test cases in jenkins builders for Tor >= 0.3.0
Starting in the 0.3.0, Tor supports fuzzing.
Now, the jenkins builders shouldn't try running the fuzzers themselves -- that consumes tons of CPU and takes forever and anyway the OSS-fuzz project is already doing that.
But we do have a unit test case that runs the testcases from the fuzzing corpora -- just once each -- to make sure that they aren't crashing or anything.
All that's needed to set this feature up on a Jenkins builder is:
Check out the git repository at https://git.torproject.org/fuzzing-corpora.git/
Any time before running "make check", set the environment variable TOR_FUZZ_CORPORA to the location of the checkout above.
This will be useful to help us prevent security regressions.