Correct if stop condition when downloading

[matt-dray]

The protocol argument check gets evaluated even when copy_type == "download" . It shouldn't. The !protocol %in% c("https", "ssh") in the if should only evaluate if copy_type == "clone" passes. So probably change & to && (preferred) or used nested ifs.

> ghdump::ghd_copy("co-analysis", "~/Desktop/co-analysis_copies", copy_type = "download")
Error in if (copy_type == "clone" & !protocol %in% c("https", "ssh")) { : 
  argument is of length zero