Code review comment for ~alexmurray/ubuntu-cve-tracker:check-syntax-support-for-kernel-patches

The commits look good! Now that I think about it, I agree that putting it in check-syntax and only applying it if there is no break-fix is the right approach.

The only thing that may need changing in the future is:

+ assert commit_hash is not None
+

I'd probably just "return []" there so that a bad upstream patch for some reason wouldn't break our triage, but I think that's unlikely to ever happen.