Reset stuck chunked uploads eventually #5344 (#5443)

Reset stuck chunked uploads eventually #5344 (#5443)

Previously this wasn't happening for errors that were not
NormalErrors because they don't end up in the blacklist.

This revises the resetting logic to be independent of the
error blacklist and make use of UploadInfo::errorCount
instead.

412 errors should reset chunked uploads because they might be
indicative of a checksum error.

Additionally, server bugs might require that additional
errors cause an upload reset. To allow that, a new capability
is added that can be used to advise the client about this.