internal/database: replace os.MkdirTemp with T.TempDir

Updates [#45402](https://go.dev/issue/45402).

Change-Id: I7e14a6923af21fd5ce4979c648734155a3468558
GitHub-Last-Rev: 81004b2
GitHub-Pull-Request: #1508
Reviewed-on: https://go-review.googlesource.com/c/vulndb/+/463098
Reviewed-by: Tatiana Bradley <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Run-TryBot: Tim King <[email protected]>
Reviewed-by: Tim King <[email protected]>

Author: alexandear

internal/database/write_test.go

@@ -6,30 +6,20 @@ package database
 
 import (
 	"fmt"
-	"os"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
 	"golang.org/x/mod/sumdb/dirhash"
 )
 
 func TestWrite(t *testing.T) {
-	tempDir, err := os.MkdirTemp("", "testWrite")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	defer func() {
-		if err := os.RemoveAll(tempDir); err != nil {
-			t.Log(err)
-		}
-	}()
+	tempDir := t.TempDir()
 
 	if err := valid.Write(tempDir, true); err != nil {
 		t.Fatal(err)
 	}
 
-	if err = cmpDirHashes(tempDir, validDir); err != nil {
+	if err := cmpDirHashes(tempDir, validDir); err != nil {
 		t.Error(err)
 	}
 }
@@ -53,16 +43,7 @@ func cmpDirHashes(d1, d2 string) error {
 
 // Check that Write and Load are inverses.
 func TestWriteLoad(t *testing.T) {
-	tempDir, err := os.MkdirTemp("", "testWriteLoad")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	defer func() {
-		if err := os.RemoveAll(tempDir); err != nil {
-			t.Log(err)
-		}
-	}()
+	tempDir := t.TempDir()
 
 	written := valid
 	if err := written.Write(tempDir, false); err != nil {