grandpa-rpc: use FinalityProofProvider to check finality for rpc (#6215)

* grandpa-rpc: use FinalityProofProvider to check finality for rpc

* grandpa-rpc: minor tidy

* grandpa-rpc: remove dyn FinalityProofProvider

* grandpa-rpc: remove unused dependencies

* node: move finality_proof_provider setup

* grandpa-rpc: print error reported by finality_proof_provider

* grandpa-rpc: add note about unnecessary encode/decode

* grandpa-rpc: dont encode/decode and use correct hash

* grandpa-rpc: set_id is optional

* grandpa-rpc: create test for prove_finality

* grandpa-rpc: set visibility back to how it was

* grandpa-rpc: remove unused dependency

* grandpa-rpc: minor tidy

* grandpa: doc strings

* grandpa-rpc: rename to prove_finality

* grandpa-rpc: use current set id if none is provided

* grandpa-rpc: remove unnecessary check in test

* node: group finality_proof_provider in rpc_setup

* grandpa: make prove_finality concrete in FinalityProofProvider

* grandpa-rpc: wrap finality output in struct and store as Bytes

* grandpa-rpc: exhaustive error codes and wrap

* grandpa-rpc: let prove_finality take a range instead of a starting point

* grandpa-rpc: fix test for changed API

* grandpa-rpc: fix line length

* grandpa: fix reviewer nits

* node/rpc: fix reviewer comments

substrate/Cargo.lock

@@ -3823,6 +3823,7 @@ dependencies = [
  "sp-blockchain",
  "sp-consensus",
  "sp-consensus-babe",
+ "sp-runtime",
  "sp-transaction-pool",
  "substrate-frame-rpc-system",
 ]
@@ -6821,6 +6822,7 @@ dependencies = [
  "log",
  "parity-scale-codec",
  "sc-block-builder",
+ "sc-client-api",
  "sc-finality-grandpa",
  "sc-network-test",
  "sc-rpc",