Make forwarding rule service_label and service_name GA (#221)

Signed-off-by: Modular Magician <magic-modules@google.com>

plugins/modules/gcp_compute_forwarding_rule_facts.py

@@ -216,6 +216,24 @@ items:
         it is assumed to be PREMIUM.'
       returned: success
       type: str
+    serviceLabel:
+      description:
+      - An optional prefix to the service name for this Forwarding Rule.
+      - If specified, will be the first label of the fully qualified service name.
+      - The label must be 1-63 characters long, and comply with RFC1035.
+      - Specifically, the label must be 1-63 characters long and match the regular
+        expression `[a-z]([-a-z0-9]*[a-z0-9])?` which means the first character must
+        be a lowercase letter, and all following characters must be a dash, lowercase
+        letter, or digit, except the last character, which cannot be a dash.
+      - This field is only used for internal load balancing.
+      returned: success
+      type: str
+    serviceName:
+      description:
+      - The internal fully qualified service name for this Forwarding Rule.
+      - This field is only used for internal load balancing.
+      returned: success
+      type: str
     region:
       description:
       - A reference to the region where the regional forwarding rule resides.