feat(alertcenter): update the api

#### alertcenter:v1beta1

The following keys were deleted:
- schemas.OutOfDomainForwarding (Total Keys: 7)

The following keys were added:
- schemas.AppsOutage (Total Keys: 10)

Author: yoshi-automation

googleapiclient/discovery_cache/documents/alertcenter.v1beta1.json

@@ -423,7 +423,7 @@
       }
     }
   },
-  "revision": "20210713",
+  "revision": "20210720",
   "rootUrl": "https://alertcenter.googleapis.com/",
   "schemas": {
     "AccountWarning": {
@@ -688,6 +688,50 @@
       },
       "type": "object"
     },
+    "AppsOutage": {
+      "description": "An outage incident reported by Google for a Google Workspace (formerly G Suite) application.",
+      "id": "AppsOutage",
+      "properties": {
+        "dashboardUri": {
+          "description": "Link to the outage event in Google Workspace Status Dashboard",
+          "type": "string"
+        },
+        "nextUpdateTime": {
+          "description": "Timestamp by which the next update shall be provided.",
+          "format": "google-datetime",
+          "type": "string"
+        },
+        "products": {
+          "description": "List of products impacted by the outage.",
+          "items": {
+            "type": "string"
+          },
+          "type": "array"
+        },
+        "resolutionTime": {
+          "description": "Timestamp of the outage expected or confirmed resolution. (Used only when known).",
+          "format": "google-datetime",
+          "type": "string"
+        },
+        "status": {
+          "description": "Current outage status.",
+          "enum": [
+            "STATUS_UNSPECIFIED",
+            "NEW",
+            "ONGOING",
+            "RESOLVED"
+          ],
+          "enumDescriptions": [
+            "Status is unspecified.",
+            "The incident has just been reported.",
+            "The incidnet is ongoing.",
+            "The incident has been resolved."
+          ],
+          "type": "string"
+        }
+      },
+      "type": "object"
+    },
     "Attachment": {
       "description": "Attachment with application-specific information about an alert.",
       "id": "Attachment",
@@ -1163,30 +1207,6 @@
       },
       "type": "object"
     },
-    "OutOfDomainForwarding": {
-      "description": "An alert that gets triggered when a user enables autoforwarding to an email which is outside of its domain",
-      "id": "OutOfDomainForwarding",
-      "properties": {
-        "actorEmail": {
-          "description": "Email of the actor who triggered the alert.",
-          "type": "string"
-        },
-        "enableTime": {
-          "description": "The time the email forwarding was enabled",
-          "format": "google-datetime",
-          "type": "string"
-        },
-        "forwardeeEmail": {
-          "description": "Email to which emails are being forwarded",
-          "type": "string"
-        },
-        "ipAddress": {
-          "description": "IP address of the user while enabling forwarding",
-          "type": "string"
-        }
-      },
-      "type": "object"
-    },
     "PhishingSpike": {
       "description": "Alert for a spike in user reported phishing. *Warning*: This type has been deprecated. Use [MailPhishing](/admin-sdk/alertcenter/reference/rest/v1beta1/MailPhishing) instead.",
       "id": "PhishingSpike",