refactor: remove legacy REST APIs (#807)

* remove legacy REST API from swagger

* feat: remove legacy REST-related things in client-side

* feat: remove legacy REST-related things in server-side

* refactor: remove all REST handlers in x modules

* refactor: remove legacy REST API in `simapp`

* refactor: remove `RegisterRESTRoutes` in all x modules

* chore: update mocks

* chore: update CHANGELOG

* remove sdk_test (legacy)

* revert mocks

* go mod tidy

* remove legact REST test in x/wasm

* remove `getBlockByHash` which was used in legacy REST

* test: modify an invalid grpc test case

* fix typo

* update statik

* go mod tidy

* goimports

* chore: add missing norace tag

* chore: combine CHANGELOG to one line

CHANGELOG.md

@@ -45,6 +45,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Bug Fixes
 
 ### Breaking Changes
+* (rest) [\#807](https://github.com/line/lbm-sdk/pull/807) remove legacy REST API
 
 ### Build, CI
 

client/docs/config.json

@@ -1,17 +1,11 @@
 {
   "swagger": "2.0",
   "info": {
-    "title": "LBM SDK - Legacy REST and gRPC Gateway docs",
+    "title": "LBM SDK - gRPC Gateway docs",
     "description": "A REST interface for state queries, legacy transactions",
     "version": "1.0.0"
   },
   "apis": [
-    {
-      "url": "./client/docs/swagger_legacy.yaml",
-      "dereference": {
-        "circular": "ignore"
-      }
-    },
     {
       "url": "./tmp-swagger-gen/cosmos/auth/v1beta1/query.swagger.json",
       "operationIds": {