fix: retrieve pool $ tvl via apiv3 instead of through subgraph

[gosuto-inzasheru]

eg https://github.com/BalancerMaxis/bal_tools/blob/88e0baee26f8ba7a3f8575836fa03d35ee8893a1/bal_tools/graphql/core/liquid_pools_protocol_yield_fee.gql#L11 but there could be more instances