Podman `get_containers()` fails against the ansible backend

[BenjaminSchubert]

When running host.podman.get_containers(), podman generates the following command that is run:

podman ps --all --format {{.Names}}

The Ansible providers interprets the {{ as the start of a jinja2 template, and thus tries to interpet it, which fails with:

self = <testinfra.backend.ansible.AnsibleBackend object at 0x7f4af339e7d0>
command = "podman ps --all --format '{{.Names}}'", args = (), kwargs = {}
host = None
out = {'msg': "template error while templating string: unexpected '.'. String: podman ps --all --format '{{.Names}}'. unexpected '.'"}

    def run(self, command, *args, **kwargs):
        command = self.get_command(command, *args)
        if not self.force_ansible:
            host = self.ansible_runner.get_host(
                self.host,
                ssh_config=self.ssh_config,
                ssh_identity_file=self.ssh_identity_file,
            )
            if host is not None:
                return host.run(command)
        out = self.run_ansible("shell", module_args=command, check=False)
        return self.result(
>           out["rc"],
            command,
            stdout_bytes=None,
            stderr_bytes=None,
            stdout=out["stdout"],
            stderr=out["stderr"],
        )
E       KeyError: 'rc'

In the meantime, host.run("podman ps --all --format '{{ '{{' }}.Names{{ '}}' }}'") works, but is a bit more manual.

I would be happy to provide a fix, but I am unsure how best to do this, given that in other cases, interpolation is what is wanted