Flake Fix: Wait before connecting container port

It was observed during periodic testing, this test can fail due to the
container process being not fully running and listening on the expected
port:

```
[+1069s] not ok 220 podman networking: port with --userns=keep-id
[+1069s] # (in test file test/system/500-networking.bats, line 144)
[+1069s] #   `echo "$teststring" | nc 127.0.0.1 $myport' failed
[+1069s] # # /var/tmp/go/src/github.com/containers/podman/bin/podman rm
--all --force
[+1069s] # # /var/tmp/go/src/github.com/containers/podman/bin/podman ps
--all --external --format {{.ID}} {{.Names}}
[+1069s] # # /var/tmp/go/src/github.com/containers/podman/bin/podman
images --all --format {{.Repository}}:{{.Tag}} {{.ID}}
[+1069s] # quay.io/libpod/testimage:20210610 9f9ec7f2fdef
[+1069s] # # /var/tmp/go/src/github.com/containers/podman/bin/podman run
-d --userns=keep-id -p 127.0.0.1:54322:54322
quay.io/libpod/testimage:20210610 nc -l -n -v -p 54322
[+1069s] #
252c562c9a3c96892d867d1d72fb52b2efdfe62855ebedbccd2d281c472c2988
[+1069s] # Ncat: No route to host.
```

Fix this by using a new `wait_for_port()` function (thanks @edsantiago)
before attempting to communicate with the service.

Signed-off-by: Chris Evich <cevich@redhat.com>

0 files changed, 0 insertions, 0 deletions