Unable to update a database user with sqladmin-v1beta4:users

The gcp-types/sqladmin-v1beta4:users interfact does not have a GET method.

When updating a big DM configuration that contains a database user resource like this:
```
resources:
# No GET method for user, resulting update error
- name: {{ env['name'] }}
type: gcp-types/sqladmin-v1beta4:users
properties:
name: {{ properties['userName'] }}
instance: {{ properties['instanceName'] }}
host: ""
password: {{ properties['password'] }}
```
There must be an update error:
```
ERROR: (gcloud.deployment-manager.deployments.update) Error in Operation [operation-1522961826387-569202eab1438-48567386-60db63f3]: errors:
- code: MISSING_METHOD_IN_COLLECTION
message: Method 'get' does not exists for collection 'users' in descriptor url 'https://www.googleapis.com/discovery/v1/apis/sqladmin/v1beta4/rest'
```

I have to remove the user configuration from that bit DM configuration