removes region param from google_compute_backend_service (#10903)

* removes region param from backend_service

- this param was not being used in this service
- you need a regional_backend_service if you want to pass this

* deprecated region instead of outright removing

* put session affinity formatting back

builtin/providers/google/resource_compute_backend_service.go

@@ -118,9 +118,10 @@ func resourceComputeBackendService() *schema.Resource {
 			},
 
 			"region": &schema.Schema{
-				Type:     schema.TypeString,
-				Optional: true,
-				ForceNew: true,
+				Type:       schema.TypeString,
+				Optional:   true,
+				ForceNew:   true,
+				Deprecated: "This parameter has been removed as it was never used",
 			},
 
 			"self_link": &schema.Schema{

website/source/docs/providers/google/r/compute_backend_service.html.markdown

@@ -86,9 +86,6 @@ The following arguments are supported:
 * `protocol` - (Optional) The protocol for incoming requests. Defaults to
     `HTTP`.
 
-* `region` - (Optional) The Region in which the created address should reside.
-    If it is not provided, the provider region is used.
-
 * `session_affinity` - (Optional) How to distribute load. Options are `NONE` (no
     affinity), `CLIENT_IP` (hash of the source/dest addresses / ports), and
     `GENERATED_COOKIE` (distribute load using a generated session cookie).
@@ -96,7 +93,6 @@ The following arguments are supported:
 * `timeout_sec` - (Optional) The number of secs to wait for a backend to respond
     to a request before considering the request failed. Defaults to `30`.
 
-
 **Backend** supports the following attributes:
 
 * `group` - (Required) The name or URI of a Compute Engine instance group