fix(storagetransfer): update the API

#### storagetransfer:v1

The following keys were changed:
- schemas.TransferJob.properties.name.description

discovery/storagetransfer-v1.json

@@ -434,7 +434,7 @@
       }
     }
   },
-  "revision": "20210325",
+  "revision": "20210408",
   "rootUrl": "https://storagetransfer.googleapis.com/",
   "schemas": {
     "AwsAccessKey": {
@@ -1034,7 +1034,7 @@
           "type": "string"
         },
         "name": {
-          "description": "A unique name (within the transfer project) assigned when the job is created. If this field is empty in a CreateTransferJobRequest, Storage Transfer Service will assign a unique name. Otherwise, the specified name is used as the unique name for this job. If the specified name is in use by a job, the creation request fails with an ALREADY_EXISTS error. This name must start with `\"transferJobs/\"` prefix and end with a letter or a number, and should be no more than 128 characters. Example: `\"transferJobs/[A-Za-z0-9-._~]*[A-Za-z0-9]$\"` Invalid job names will fail with an INVALID_ARGUMENT error.",
+          "description": "A unique name (within the transfer project) assigned when the job is created. If this field is empty in a CreateTransferJobRequest, Storage Transfer Service will assign a unique name. Otherwise, the specified name is used as the unique name for this job. If the specified name is in use by a job, the creation request fails with an ALREADY_EXISTS error. This name must start with `\"transferJobs/\"` prefix and end with a letter or a number, and should be no more than 128 characters. This name must not start with 'transferJobs/OPI'. 'transferJobs/OPI' is a reserved prefix. Example: `\"transferJobs/^(?!OPI)[A-Za-z0-9-._~]*[A-Za-z0-9]$\"` Invalid job names will fail with an INVALID_ARGUMENT error.",
           "type": "string"
         },
         "notificationConfig": {

src/apis/storagetransfer/v1.ts

@@ -548,7 +548,7 @@ export namespace storagetransfer_v1 {
      */
     latestOperationName?: string | null;
     /**
-     * A unique name (within the transfer project) assigned when the job is created. If this field is empty in a CreateTransferJobRequest, Storage Transfer Service will assign a unique name. Otherwise, the specified name is used as the unique name for this job. If the specified name is in use by a job, the creation request fails with an ALREADY_EXISTS error. This name must start with `"transferJobs/"` prefix and end with a letter or a number, and should be no more than 128 characters. Example: `"transferJobs/[A-Za-z0-9-._~]*[A-Za-z0-9]$"` Invalid job names will fail with an INVALID_ARGUMENT error.
+     * A unique name (within the transfer project) assigned when the job is created. If this field is empty in a CreateTransferJobRequest, Storage Transfer Service will assign a unique name. Otherwise, the specified name is used as the unique name for this job. If the specified name is in use by a job, the creation request fails with an ALREADY_EXISTS error. This name must start with `"transferJobs/"` prefix and end with a letter or a number, and should be no more than 128 characters. This name must not start with 'transferJobs/OPI'. 'transferJobs/OPI' is a reserved prefix. Example: `"transferJobs/^(?!OPI)[A-Za-z0-9-._~]*[A-Za-z0-9]$"` Invalid job names will fail with an INVALID_ARGUMENT error.
      */
     name?: string | null;
     /**