go.mod, vendor: update (#3358)

* go.mod, vendor: remove unnecessary dependencies

Commands:
1. go mod tidy
2. go mod vendor

* go.mod, vendor: update cloud.google.com/go

Commands:
1. go get -u cloud.google.com/go
2. go mod tidy
3. go mod vendor

* go.mod, vendor: update cloud.google.com/*

Commands:
1. go get -u cloud.google.com/storage cloud.google.com/logging
2. go mod tidy
3. go mod vendor

* go.mod, .golangci.yml, vendor: update *lint*

Commands:
1. go get -u golang.org/x/tools github.com/golangci/golangci-lint@v1.47.0
2. go mod tidy
3. go mod vendor
4. edit .golangci.yml to suppress new errors (resolved in the same PR later)

* all: fix lint errors

hash.go: copy() recommended by gosimple
parse.go: ent is never nil
verifier.go: signal.Notify() with unbuffered channel is bad. Have no idea why.

* .golangci.yml: adjust godot rules

check-all is deprecated, but still work
if you're hesitating too - I'll remove this commit

3 files changed, 11 insertions, 5 deletions

diff --git a/vendor/github.com/nakabonne/nestif/README.md b/vendor/github.com/nakabonne/nestif/README.md
index ede411f73..37d370175 100644
--- a/vendor/github.com/nakabonne/nestif/README.md
+++ b/vendor/github.com/nakabonne/nestif/README.md
@@ -2,16 +2,22 @@
 
 [![Go Doc](https://img.shields.io/badge/godoc-reference-blue.svg?style=flat-square)](http://godoc.org/github.com/nakabonne/nestif)
 
-Reports deeply nested if statements in Go code, by calculating its complexities based on the rules defined by the [Cognitive Complexity white paper by G. Ann Campbell](https://www.sonarsource.com/docs/CognitiveComplexity.pdf).
+Reports complex nested if statements in Go code, by calculating its complexities based on the rules defined by the [Cognitive Complexity white paper by G. Ann Campbell](https://www.sonarsource.com/docs/CognitiveComplexity.pdf).
 
 It helps you find if statements that make your code hard to read, and clarifies which parts to refactor.
 
 ## Installation
 
+### By go get
+
 ```
 go get github.com/nakabonne/nestif/cmd/nestif
 ```
 
+### By golangci-lint
+
+`nestif` is already integrated with [golangci-lint](https://github.com/golangci/golangci-lint). Please refer to the instructions there and enable it.
+
 ## Usage
 
 ### Quick Start
diff --git a/vendor/github.com/nakabonne/nestif/go.mod b/vendor/github.com/nakabonne/nestif/go.mod
index 325901d59..0d5b1f721 100644
--- a/vendor/github.com/nakabonne/nestif/go.mod
+++ b/vendor/github.com/nakabonne/nestif/go.mod
@@ -1,6 +1,6 @@
 module github.com/nakabonne/nestif
 
-go 1.13
+go 1.15
 
 require (
 	github.com/spf13/pflag v1.0.5
diff --git a/vendor/github.com/nakabonne/nestif/nestif.go b/vendor/github.com/nakabonne/nestif/nestif.go
index d458022fb..c4bad7f2d 100644
--- a/vendor/github.com/nakabonne/nestif/nestif.go
+++ b/vendor/github.com/nakabonne/nestif/nestif.go
@@ -1,10 +1,10 @@
-// Copyright 2020 Ryo Nakao <nakabonne@gmail.com>.
+// Copyright 2020 Ryo Nakao <ryo@nakao.dev>.
 //
 // All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package nestif provides an API to detect deeply nested if statements.
+// Package nestif provides an API to detect complex nested if statements.
 package nestif
 
 import (
@@ -133,7 +133,7 @@ func (c *Checker) makeMessage(complexity int, cond ast.Expr, fset *token.FileSet
 	if err := p.Fprint(b, fset, cond); err != nil {
 		c.debug("failed to convert condition into string: %v", err)
 	}
-	return fmt.Sprintf("`if %s` is deeply nested (complexity: %d)", b.String(), complexity)
+	return fmt.Sprintf("`if %s` has complex nested blocks (complexity: %d)", b.String(), complexity)
 }
 
 // DebugMode makes it possible to emit debug logs.