artifactregistry: missing fields in `artifactregistrypb.Registry`

**Client**

Importing the project and using the grpc client for making requests.

**Environment**

Local development, N/A

**Go Environment**

$ go version: go version go1.20.5 linux/amd64
$ go env N/A

**Code**

Related to this struct:

https://github.com/googleapis/google-cloud-go/blob/c7e8fd1c0d15c595d01fc354cdd0db709d6f9aaf/artifactregistry/apiv1/artifactregistrypb/repository.pb.go#L166-L198

**Expected behavior**

According to both [the documentation](https://cloud.google.com/artifact-registry/docs/reference/rpc/google.devtools.artifactregistry.v1#google.devtools.artifactregistry.v1.Repository) and the actual REST calls, the `Repository` data model returns some fields like `sizeBytes` or `mode`. For instance, this is a real call I have just performed:

```json
{
"name": "projects/my-foo-project-id/locations/us-east1/repositories/my-cool-repo-id",
"format": "DOCKER",
"createTime": "2023-05-16T16:12:52.205145Z",
"updateTime": "2023-05-16T16:12:52.205145Z",
"mode": "STANDARD_REPOSITORY",
"sizeBytes": "61885866"
}

```

**Actual behavior**

Some fields appearing in the [documentation](https://cloud.google.com/artifact-registry/docs/reference/rpc/google.devtools.artifactregistry.v1#google.devtools.artifactregistry.v1.Repository) are not being mapped to the GRPC message, therefore, they are not easily available when using the gcloud go SDK.

Specifically, I miss the following fields:

- `mode`
- `sizeBytes`
- `satisfiesPzs` (this is not being even returned in the REST API, but it is documented in the [docs site](https://cloud.google.com/artifact-registry/docs/reference/rpc/google.devtools.artifactregistry.v1#google.devtools.artifactregistry.v1.Repository))

**Additional context**

The problem applies to both `artifactregistry.apiv1beta2` and `artifactregistry.apiv1`.