chore: check blockhash/txhash length whether it is 64 (Finschia#699)

* chore: check txhash length whether it is 64

Keep the case where txhash is empty to convey more detailed messages to the user.

* chore: check blockhash length whether it is 64

* update tc to cover new logic

* chore: change `GetByBlockHash` endpoint

* test: add tc about `GetByBlockHash`

* test: add more cases to match coverage to 100%

* chore: goimports

* chore: write to CHANGELOG

* chore: turn off REST test

Unlike gRPC, REST requests often fail. Need to understand the cause later

* chore: update statik to resolve conflict

* chore: change magic number to constant in hash check

CHANGELOG.md

@@ -73,6 +73,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (refactor) [\#685](https://github.com/line/lbm-sdk/pull/685) remove x/foundation UpdateValidatorAuthsProposal
 * (x/foundation) [\#686](https://github.com/line/lbm-sdk/pull/686) remove `Minthreshold` and `MinPercentage` from x/foundation config
 * (x/foundation) [\#693](https://github.com/line/lbm-sdk/pull/693) add pool to the state of x/foundation
+* (x/auth, client) [\#699](https://github.com/line/lbm-sdk/pull/699) Improvement on input validation of `req.Hash`
 * (x/wasm,distribution) [\#696](https://github.com/line/lbm-sdk/pull/696) x/wasm,distribution - add checking a file size before reading it
 * (x/foundation) [\#698](https://github.com/line/lbm-sdk/pull/698) update x/group relevant logic in x/foundation
 * (x/auth,bank,foundation,wasm) [\#691](https://github.com/line/lbm-sdk/pull/691) change AccAddressFromBech32 to MustAccAddressFromBech32

client/grpc/tmservice/service.go

@@ -2,14 +2,14 @@ package tmservice
 
 import (
 	"context"
+	"crypto/sha256"
 
 	gogogrpc "github.com/gogo/protobuf/grpc"
 	"github.com/grpc-ecosystem/grpc-gateway/runtime"
+	abci "github.com/line/ostracon/abci/types"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 
-	abci "github.com/line/ostracon/abci/types"
-
 	"github.com/line/lbm-sdk/client"
 	"github.com/line/lbm-sdk/client/rpc"
 	codectypes "github.com/line/lbm-sdk/codec/types"
@@ -88,6 +88,13 @@ func (s queryServer) GetBlockByHeight(ctx context.Context, req *GetBlockByHeight
 
 // GetBlockByHash implements ServiceServer.GetBlockByHash
 func (s queryServer) GetBlockByHash(_ context.Context, req *GetBlockByHashRequest) (*GetBlockByHashResponse, error) {
+	if n := len(req.Hash); n != sha256.Size {
+		if n == 0 {
+			return nil, status.Error(codes.InvalidArgument, "block hash cannot be empty")
+		}
+		return nil, status.Error(codes.InvalidArgument, "The length of blcok hash must be 32")
+	}
+
 	res, err := getBlockByHash(s.clientCtx, req.Hash)
 	if err != nil {
 		return nil, err