fix: workaround podman bug wrt error reporting (#3478)

In case that the image registry hostname is not resolvable podman now
return error in bad JSON shape so it's not decodable by client.

For now we assume that '500.*but provided no error-message' means
hostname resolution error.

Signed-off-by: Matej Vašek <matejvasek@gmail.com>
Co-authored-by: Matej Vašek <matejvasek@gmail.com>

Author: knative-prow-robot

pkg/docker/pusher.go

@@ -194,7 +194,8 @@ func (n *Pusher) pushImage(ctx context.Context, f fn.Function, credentials oci.C
 	errStr := err.Error()
 	if strings.Contains(errStr, "no such host") ||
 		strings.Contains(errStr, "failure in name resolution") ||
-		regexp.MustCompile(`lookup .*: server misbehaving`).MatchString(errStr) {
+		regexp.MustCompile(`lookup .*: server misbehaving`).MatchString(errStr) ||
+		regexp.MustCompile(`500.*but provided no error-message`).MatchString(errStr) {
 		// push with custom transport to be able to push into cluster private registries
 		return n.push(ctx, f, credentials, output)
 	}