run golangci-lint and apply suggested fixes

config/config_test.go

@@ -39,6 +39,7 @@ func TestSampleConfigsAreParsedWithoutErrors(t *testing.T) {
 }
 
 // template must be a template/text template with a single '{{ . }}' as placehodler for val
+//nolint[:deadcode,unused]
 func testValidConfigTemplate(t *testing.T, tmpl string, val string) *Config {
 	tmp, err := template.New("master").Parse(tmpl)
 	if err != nil {

config/retentiongrid.go

@@ -31,10 +31,6 @@ func (i *RetentionInterval) KeepCount() int {
 
 const RetentionGridKeepCountAll int = -1
 
-type RetentionGrid struct {
-	intervals []RetentionInterval
-}
-
 func (t *RetentionIntervalList) UnmarshalYAML(u func(interface{}, bool) error) (err error) {
 	var in string
 	if err := u(&in, true); err != nil {