Feature/gofumpt (#1545)

* enable gofumpt
* remove nlreturn
* up golang-ci

.golangci.yml

@@ -17,5 +17,5 @@ linters:
     - gomnd
     - goerr113
     - exhaustive
-    - gofumpt
     - nestif
+    - nlreturn

.travis.yml

@@ -17,4 +17,4 @@ go_import_path: github.com/go-redis/redis
 
 before_install:
   - curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s --
-    -b $(go env GOPATH)/bin v1.28.3
+    -b $(go env GOPATH)/bin v1.31.0

ring.go

@@ -13,7 +13,6 @@ import (
 
 	"github.com/cespare/xxhash/v2"
 	"github.com/dgryski/go-rendezvous"
-
 	"github.com/go-redis/redis/v8/internal"
 	"github.com/go-redis/redis/v8/internal/hashtag"
 	"github.com/go-redis/redis/v8/internal/pool"