topology: replace 'foo' in the tests with a hostname that fails (#3786)
topology: replace 'foo' in the tests with a hostname that fails (#3786)

`foo` is used in a test to represent a name that will fail to resolve. It exists sometimes (e.g. in the ETH).

Change it to some more weird name so it fails resolving it.
Oncilla/scion,Oncilla/scion,netsec-ethz/scion,Oncilla/scion,netsec-ethz/scion,netsec-ethz/scion,netsec-ethz/scion,Oncilla/scion