Extension resource: `azurerm_monitor_data_collection_rule_association` not discovered

The `azurerm_monitor_data_collection_rule_association` is different than the other `_association` resources, in that it is a real azure resource, whilst it is an *extension* resource that can be derived in a couple of different resource types. This is similar to role assignment resources (also is an *extension* resource). The way we are handling the *extension* resource in terms of discoverability is to use instruct `azlist` to try to list the specified extension resource types, which can cause performance downgrade. Hence we let the user to decide whether to include a certain type of extension resource, via `--include-role-assignment`. This means we probably need to introduce a similar option `--include-monitor-data-collection-rule-association` for this case (the option is so long..). Apparently, this is not a scalable way to handle that. Instead, we probably shall consider to introduce an option `--include-extension-resource="rt1,rt2"` to ask the users to specify that extension resources (as how `aztfexport` calls `azlist`). Though this can be tedius and hard to use.

Besides, the current ARM schema file doesn't include the record for this resource type, which is tracked by https://github.com/Azure/azure-resource-manager-schemas/issues/3526.