refactor: replace uses of ioutil with io and os (#223)

pkg/jsonnet/decode.go

@@ -3,7 +3,6 @@ package jsonnet
 import (
 	"encoding/json"
 	"io"
-	"io/ioutil"
 
 	"github.com/google/go-jsonnet"
 )
@@ -20,7 +19,7 @@ func NewDecoder(r io.Reader) *Decoder {
 
 // Decode decodes the stream into the provide value.
 func (d *Decoder) Decode(v interface{}) error {
-	b, err := ioutil.ReadAll(d.r)
+	b, err := io.ReadAll(d.r)
 	if err != nil {
 		return err
 	}