lfs: narrow the exceptions that trigger a transfer retry The retries were added to workaround TCP RESETs in fb-experimental fc8c131314a9. I have no idea if that's been debugged yet, but this wide net caught local I/O errors, bad hostnames and other things that shouldn't be retried. The next patch will validate objects as they are uploaded, and there's no need to retry those errors. The spec[1] does mention that certain http errors can be retried, including 500. But let's work through the corruption detection issues first. [1] https://github.com/git-lfs/git-lfs/blob/master/docs/api/batch.md