Replace deprecated ioutil with io and os (#20776)

* Replace ioutil with io and os

* Replace ioutil in utils/file.go

* Minor fix to tests and excluded files

Co-authored-by: Tim Scheuermann <tim.scheuermann@mattermost.com>
Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/users/helper_test.go

@@ -5,7 +5,6 @@ package users
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -48,7 +47,7 @@ func Setup(tb testing.TB) *TestHelper {
 }
 
 func setupTestHelper(s store.Store, includeCacheLayer bool, tb testing.TB) *TestHelper {
-	tempWorkspace, err := ioutil.TempDir("", "userservicetest")
+	tempWorkspace, err := os.MkdirTemp("", "userservicetest")
 	if err != nil {
 		panic(err)
 	}

app/users/profile_picture.go

@@ -11,7 +11,7 @@ import (
 	"image/draw"
 	"image/png"
 	"io"
-	"io/ioutil"
+	"os"
 	"path"
 	"path/filepath"
 	"strings"
@@ -174,7 +174,7 @@ func getFont(initialFont string) (*truetype.Font, error) {
 	}
 
 	fontDir, _ := fileutils.FindDir("fonts")
-	fontBytes, err := ioutil.ReadFile(filepath.Join(fontDir, initialFont))
+	fontBytes, err := os.ReadFile(filepath.Join(fontDir, initialFont))
 	if err != nil {
 		return nil, err
 	}