refactor: move from io/ioutil to io and os package

The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.

Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

connector/bitbucketcloud/bitbucketcloud.go

@@ -6,7 +6,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"sync"
 	"time"
@@ -453,7 +453,7 @@ func get(ctx context.Context, client *http.Client, apiURL string, v interface{})
 	defer resp.Body.Close()
 
 	if resp.StatusCode != http.StatusOK {
-		body, err := ioutil.ReadAll(resp.Body)
+		body, err := io.ReadAll(resp.Body)
 		if err != nil {
 			return fmt.Errorf("bitbucket: read body: %s: %v", resp.Status, err)
 		}