add grpc support for delete client

[ashwanthgoli]

Is your feature request related to a problem? Please describe.
To perform query filtering, queriers make HTTP calls to compactor for fetching delete requests.
Ideally we want to use gRPC for interservice communication and users can work with the HTTP api for managing delete requests.

Describe the solution you'd like
Add gRPC methods for fetching delete requests and generation numbers, use these methods in querier

Describe alternatives you've considered
NA

Additional context
NA

[periklis]

@ashwanthgoli This is something I hit when fixing the client's TLS config (See #7453). We decided within the maintainers group to implement this post-releasing v2.7.0.