rename LB field in the compose file

Signed-off-by: aiordache <[email protected]>
Signed-off-by: Nicolas De Loof <[email protected]>

ecs/pkg/amazon/x.go

@@ -4,5 +4,5 @@ const (
 	ExtensionSecurityGroup   = "x-aws-securitygroup"
 	ExtensionVPC             = "x-aws-vpc"
 	ExtensionPullCredentials = "x-aws-pull_credentials"
-	ExtensionLB              = "x-aws-lb"
+	ExtensionLB              = "x-aws-loadbalancer"
 )