When node name contains vertical bar symbol some commands output is
garbled because `|` is used as a delimiter in `columnize.SimpleFormat`.
This commit changes format string to use `\x1f` - ASCII unit
separator[1] as a delimiter and also adds test to cover this case.
Affected commands:
* `consul catalog nodes`
* `consul members`
* `consul operator raft list-peers`
* `consul intention get`
Fixes#3951.
[1]: https://en.wikipedia.org/wiki/Delimiter#Solutions
This way we can avoid unnecessary panics which cause other tests not to run.
This doesn't remove all the possibilities for panics causing other tests not to run, it just fixes the TestAgent
