Handle ioutil deprecations (#53526)

* replace ioutil.ReadFile -> os.ReadFile

* replace ioutil.ReadAll -> io.ReadAll

* replace ioutil.TempFile -> os.CreateTemp

* replace ioutil.NopCloser -> io.NopCloser

* replace ioutil.WriteFile -> os.WriteFile

* replace ioutil.TempDir -> os.MkdirTemp

* replace ioutil.Discard -> io.Discard

pkg/tsdb/cloudmonitoring/cloudmonitoring.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"math"
 	"net/http"
 	"net/url"
@@ -627,7 +626,7 @@ func (s *Service) getDefaultProject(ctx context.Context, dsInfo datasourceInfo)
 }
 
 func unmarshalResponse(res *http.Response) (cloudMonitoringResponse, error) {
-	body, err := ioutil.ReadAll(res.Body)
+	body, err := io.ReadAll(res.Body)
 	if err != nil {
 		return cloudMonitoringResponse{}, err
 	}

pkg/tsdb/cloudmonitoring/resource_handler.go

@@ -7,7 +7,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"regexp"
@@ -216,7 +215,7 @@ func decode(encoding string, original io.ReadCloser) ([]byte, error) {
 		return nil, fmt.Errorf("unexpected encoding type %v", err)
 	}
 
-	body, err := ioutil.ReadAll(reader)
+	body, err := io.ReadAll(reader)
 	if err != nil {
 		return nil, err
 	}

pkg/tsdb/cloudmonitoring/resource_handler_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -78,7 +78,7 @@ func Test_doRequest(t *testing.T) {
 		t.Errorf("Unexpected headers: %v", res.Header())
 	}
 	result := rw.Result()
-	body, err := ioutil.ReadAll(result.Body)
+	body, err := io.ReadAll(result.Body)
 	if err != nil {
 		t.Error(err)
 	}

pkg/tsdb/cloudmonitoring/time_series_filter_test.go

@@ -3,9 +3,9 @@ package cloudmonitoring
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
 	"math"
 	"net/url"
+	"os"
 	"strconv"
 	"testing"
 	"time"
@@ -479,7 +479,7 @@ func loadTestFile(path string) (cloudMonitoringResponse, error) {
 
 	// Can ignore gosec warning G304 here since it's a test path
 	// nolint:gosec
-	jsonBody, err := ioutil.ReadFile(path)
+	jsonBody, err := os.ReadFile(path)
 	if err != nil {
 		return data, err
 	}