Pull request: imp-tests

Merge in DNS/adguard-home from imp-tests to master

Squashed commit of the following:

commit ea5b4e7a93359ae4800f75e77d02944a4f5d2df8
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Oct 27 15:12:45 2022 +0300

    all: imp tests, use testutil

internal/aghtest/aghtest.go

@@ -3,23 +3,11 @@ package aghtest
 
 import (
 	"io"
-	"os"
 	"testing"
 
 	"github.com/AdguardTeam/golibs/log"
 )
 
-// DiscardLogOutput runs tests with discarded logger output.
-//
-// TODO(a.garipov): Replace with testutil.
-func DiscardLogOutput(m *testing.M) {
-	// TODO(e.burkov): Refactor code and tests to not use the global mutable
-	// logger.
-	log.SetOutput(io.Discard)
-
-	os.Exit(m.Run())
-}
-
 // ReplaceLogWriter moves logger output to w and uses Cleanup method of t to
 // revert changes.
 func ReplaceLogWriter(t testing.TB, w io.Writer) {