Fix warnings in logs when gridftp block not present
Begin arcbot message
This merge request is automatically copied from !529 (merged) orginally made by @floridop
End arcbot message
## Fix warnings in logs when gridftp block not present
Description
Some lines of code in ARC[0|1]ClusterInfo.pm did not check if the gridftpd block was defined or not generating perl warnings. This is now fixed