Loki: Add support for query filters in list_loki_label_values

[srikarduplo]

Currently, the list_loki_label_values function retrieves label values without allowing any query-based filtering.

For example, it’s not possible to fetch label values (e.g., service) limited to a specific namespace.

According to the Loki API documentation, the /label/{name}/values endpoint supports an optional query parameter that can be used for such filtering.

Adding support for the query parameter in list_loki_label_values would make it possible to narrow down label values based on specific criteria (like namespace, job, or other labels).

[rahulvijil]

Here is the fix for the above #380