fix warning message in rep logs

[romain-dartigues]

Summary

Remove mutually-exclusive xargs options which are generating warnings in the logs.

Describe alternatives you've considered (optional)

I favored the -I {} over the -n1 for, arguably, readability.

I would have suggested to use awk '$2 ~ "'$old_shared_data_dir'"{print $2}' /proc/mounts… over mount | grep $old_shared_data_dir | cut -d' ' -f3…, but since it's a personal preference and does not relate to the current issue, I left it out.

Additional Text Output, Screenshots, or contextual information (optional)

The /var/vcap/data/sys/log/rep/rep.stderr.log contains the warning:

xargs: warning: options --max-args and --replace/-I/-i are mutually exclusive, ignoring previous --max-args value