let with-lock specify the lockfile to use directly

[terefang]

sometimes multiple different commands might compete of one lock, in that case it is necessary to have a well-known lock-file.

/path/to/sysbox with-lock -prefix /var/tmp/ -lockfile processing-lock-group1 /path/to/command1 [flags1]

/path/to/sysbox with-lock -prefix /var/tmp/ -lockfile processing-lock-group1 /path/to/command2 [flags2]

/path/to/sysbox with-lock -prefix /var/tmp/ -lockfile processing-lock-group2 /path/to/command3 [flags3]

/path/to/sysbox with-lock -prefix /var/tmp/ -lockfile processing-lock-group2 /path/to/command4 [flags4]

in the example above cmd1 and cmd2 are sharing lock-group1 and cmd3 and cmd4 are sharing lock-group2