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/prometheus/client/client_test.go

@@ -2,7 +2,7 @@ package client
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"testing"
 
@@ -49,7 +49,7 @@ func TestClient(t *testing.T) {
 			require.NoError(t, err)
 			require.NotNil(t, doer.Req)
 			require.Equal(t, http.MethodPost, doer.Req.Method)
-			body, err := ioutil.ReadAll(doer.Req.Body)
+			body, err := io.ReadAll(doer.Req.Body)
 			require.NoError(t, err)
 			require.Equal(t, []byte("match%5B%5D: ALERTS\nstart: 1655271408\nend: 1655293008"), body)
 			require.Equal(t, "http://localhost:9090/api/v1/series", doer.Req.URL.String())
@@ -74,7 +74,7 @@ func TestClient(t *testing.T) {
 			require.NoError(t, err)
 			require.NotNil(t, doer.Req)
 			require.Equal(t, http.MethodGet, doer.Req.Method)
-			body, err := ioutil.ReadAll(doer.Req.Body)
+			body, err := io.ReadAll(doer.Req.Body)
 			require.NoError(t, err)
 			require.Equal(t, []byte{}, body)
 			require.Equal(t, "http://localhost:9090/api/v1/series?match%5B%5D=ALERTS&start=1655272558&end=1655294158", doer.Req.URL.String())

pkg/tsdb/prometheus/querydata/framing_test.go

@@ -5,7 +5,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -124,7 +124,7 @@ func runQuery(response []byte, q *backend.QueryDataRequest, wide bool) (*backend
 	}
 	res := &http.Response{
 		StatusCode: 200,
-		Body:       ioutil.NopCloser(bytes.NewReader(response)),
+		Body:       io.NopCloser(bytes.NewReader(response)),
 	}
 	tCtx.httpProvider.setResponse(res)
 	return tCtx.queryData.Execute(context.Background(), q)

pkg/tsdb/prometheus/querydata/prometeus_bench_test.go

@@ -5,7 +5,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"net/http"
 	"strings"
@@ -29,7 +29,7 @@ func BenchmarkJson(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		res := http.Response{
 			StatusCode: 200,
-			Body:       ioutil.NopCloser(bytes.NewReader(body)),
+			Body:       io.NopCloser(bytes.NewReader(body)),
 		}
 		tCtx.httpProvider.setResponse(&res)
 		_, err := tCtx.queryData.Execute(context.Background(), q)

pkg/tsdb/prometheus/querydata/request_test.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
-	"io/ioutil"
+	"io"
 	"math"
 	"net/http"
 	"testing"
@@ -388,7 +388,7 @@ func toAPIResponse(d interface{}) (*http.Response, error) {
 
 	return &http.Response{
 		StatusCode: 200,
-		Body:       ioutil.NopCloser(bytes.NewReader(raw)),
+		Body:       io.NopCloser(bytes.NewReader(raw)),
 	}, nil
 }
 
@@ -405,7 +405,7 @@ func setup(wideFrames bool) (*testContext, error) {
 		},
 		res: &http.Response{
 			StatusCode: 200,
-			Body:       ioutil.NopCloser(bytes.NewReader([]byte(`{}`))),
+			Body:       io.NopCloser(bytes.NewReader([]byte(`{}`))),
 		},
 	}
 	settings := backend.DataSourceInstanceSettings{