Partial Set Security: Introduce queries

[insumity]

Problem

Introduce (or modify) queries as outlined in ADR-015. This means, at least the following queries:

• modify interchain-security-pd query provider list-consumer-chains to return information on whether a consumer chain is an Opt In or a Top N chain and with what N;
• interchain-security-pd query provider optedInValidators $chainID to retrieve the validators that are opted in and hence the validators that need to validate the consumer chain;
• interchain-security-pd query provider hasToValidate $providerAddr that given a validator's address returns all the chains this validator has to validate. (FYI, a note mentioned by @sainoe was that: i) we could create and store a reverse mapping on the Hub from validator to chains but this would be error prone (e.g., more code), and ii) we could just loop through all the chains and find the validator which would slow down those operations).

Closing criteria

Implement and thoroughly test.