Upgrade golangci-lint to v1.20.0

Author: chenrui333

.golangci.yml

@@ -11,8 +11,3 @@ linters-settings:
     # the regex is used to ignore names within pkg. (default "fmt:.*").
     # see https://github.com/kisielk/errcheck#the-deprecated-method for details
     ignore: fmt:.*,github.com/go-kit/kit/log:.*
-
-issues:
-  exclude:
-  - "not declared by package utf8"
-  - "unicode/utf8/utf8.go"

hack/get_lint_deps.sh

@@ -3,5 +3,5 @@ set -v
 
 go get -u golang.org/x/tools/cmd/goimports
 go get -u golang.org/x/lint/golint
-go get github.com/golangci/golangci-lint/cmd/golangci-lint@v1.17.1
+go get github.com/golangci/golangci-lint/cmd/golangci-lint@v1.20.0
 go get -u github.com/gordonklaus/ineffassign