change temp file handling function

[kflemin]

No description provided.

[nllong]

Yeah, I think the intermittent errors is caused by NOAA! I think we need to catch it better int he bsyncr code...

This is from the CI log.

613.7 Error in curl::curl_fetch_disk(x$url$url, x$disk, handle = x$url$handle) : 
613.7   Timeout was reached [ftp.ncdc.noaa.gov]: Operation timed out after 10002 milliseconds with 0 bytes received

[kflemin]

ah interesting! there seems to be a problem with getting the error log out of bsyncr-server and into a response for SEED anyway though. Agree that we should handle this better!