Errors thrown during uploadChunk are leading to a variety of uncaught errors, including:

• Error: Cache upload failed becaues the file read failed with EBADF: bad file descriptor, read
• Error: Cache upload failed because file read failed with ESPIPE: invalid seek, read

These errors cause the cache step to fail, whereas we expect caching to fail gracefully and not break a workflow.

I discuss a hypothesis for why this happens in #399 (comment), namely that:

1. Some error happens during the call to uploadChunk, in this case it was a 503 response
2. That error causes the finally block to execute and close the file descriptor
3. Closing the file descriptor kills the other in-progress calls to uploadChunk, resulting in the Error: Cache upload failed becaues the file read failed with EBADF: bad file descriptor, read