fix(pubsub): update the API

#### pubsub:v1beta1a

The following keys were changed:
- auth.oauth2.scopes.https://www.googleapis.com/auth/cloud-platform.description

#### pubsub:v1beta2

The following keys were changed:
- auth.oauth2.scopes.https://www.googleapis.com/auth/cloud-platform.description

#### pubsub:v1

The following keys were changed:
- auth.oauth2.scopes.https://www.googleapis.com/auth/cloud-platform.description
- schemas.Subscription.properties.retainAckedMessages.description

discovery/pubsub-v1.json

@@ -3,7 +3,7 @@
     "oauth2": {
       "scopes": {
         "https://www.googleapis.com/auth/cloud-platform": {
-          "description": "View and manage your data across Google Cloud Platform services"
+          "description": "See, edit, configure, and delete your Google Cloud Platform data"
         },
         "https://www.googleapis.com/auth/pubsub": {
           "description": "View and manage Pub/Sub topics and subscriptions"
@@ -1424,7 +1424,7 @@
       }
     }
   },
-  "revision": "20210225",
+  "revision": "20210322",
   "rootUrl": "https://pubsub.googleapis.com/",
   "schemas": {
     "AcknowledgeRequest": {
@@ -2048,7 +2048,7 @@
           "description": "If push delivery is used with this subscription, this field is used to configure it. An empty `pushConfig` signifies that the subscriber will pull and ack messages using API methods."
         },
         "retainAckedMessages": {
-          "description": "Indicates whether to retain acknowledged messages. If true, then messages are not expunged from the subscription's backlog, even if they are acknowledged, until they fall out of the `message_retention_duration` window. This must be true if you would like to [Seek to a timestamp] (https://cloud.google.com/pubsub/docs/replay-overview#seek_to_a_time).",
+          "description": "Indicates whether to retain acknowledged messages. If true, then messages are not expunged from the subscription's backlog, even if they are acknowledged, until they fall out of the `message_retention_duration` window. This must be true if you would like to [`Seek` to a timestamp] (https://cloud.google.com/pubsub/docs/replay-overview#seek_to_a_time) in the past to replay previously-acknowledged messages.",
           "type": "boolean"
         },
         "retryPolicy": {

discovery/pubsub-v1beta1a.json

@@ -3,7 +3,7 @@
     "oauth2": {
       "scopes": {
         "https://www.googleapis.com/auth/cloud-platform": {
-          "description": "View and manage your data across Google Cloud Platform services"
+          "description": "See, edit, configure, and delete your Google Cloud Platform data"
         },
         "https://www.googleapis.com/auth/pubsub": {
           "description": "View and manage Pub/Sub topics and subscriptions"
@@ -457,7 +457,7 @@
       }
     }
   },
-  "revision": "20200807",
+  "revision": "20210322",
   "rootUrl": "https://pubsub.googleapis.com/",
   "schemas": {
     "AcknowledgeRequest": {

discovery/pubsub-v1beta2.json

@@ -3,7 +3,7 @@
     "oauth2": {
       "scopes": {
         "https://www.googleapis.com/auth/cloud-platform": {
-          "description": "View and manage your data across Google Cloud Platform services"
+          "description": "See, edit, configure, and delete your Google Cloud Platform data"
         },
         "https://www.googleapis.com/auth/pubsub": {
           "description": "View and manage Pub/Sub topics and subscriptions"
@@ -724,7 +724,7 @@
       }
     }
   },
-  "revision": "20201110",
+  "revision": "20210322",
   "rootUrl": "https://pubsub.googleapis.com/",
   "schemas": {
     "AcknowledgeRequest": {

src/apis/pubsub/v1.ts

@@ -588,7 +588,7 @@ export namespace pubsub_v1 {
      */
     pushConfig?: Schema$PushConfig;
     /**
-     * Indicates whether to retain acknowledged messages. If true, then messages are not expunged from the subscription's backlog, even if they are acknowledged, until they fall out of the `message_retention_duration` window. This must be true if you would like to [Seek to a timestamp] (https://cloud.google.com/pubsub/docs/replay-overview#seek_to_a_time).
+     * Indicates whether to retain acknowledged messages. If true, then messages are not expunged from the subscription's backlog, even if they are acknowledged, until they fall out of the `message_retention_duration` window. This must be true if you would like to [`Seek` to a timestamp] (https://cloud.google.com/pubsub/docs/replay-overview#seek_to_a_time) in the past to replay previously-acknowledged messages.
      */
     retainAckedMessages?: boolean | null;
     /**