Pull request: all: imp errcheck in tests

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

Squashed commit of the following:

commit ed046b8ef59a092a27c623cd14b3fc2ef305fc3d
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Feb 4 15:00:04 2021 +0300

    stats: imp cleanup more

commit e53a9240d3e3eec2417c768b98c267a8cd54d992
Merge: da734317 676f8c76
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Feb 4 14:59:40 2021 +0300

    Merge branch 'master' into imp-errcheck

commit da734317035543b52e5a9030813084bdc92ba90a
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Feb 4 14:37:26 2021 +0300

    stats: imp cleanup

commit 8b4ad150129111a09be6fa2944a21bd06ab8e5a1
Merge: 385c8a6c 5081ead0
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Feb 4 14:34:26 2021 +0300

    Merge branch 'master' into imp-errcheck

commit 385c8a6c91e3bf07a457da370c8cc77820b91600
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Fri Jan 29 20:41:57 2021 +0300

    all: imp errcheck in tests

internal/home/auth_test.go

@@ -79,7 +79,6 @@ func TestAuth(t *testing.T) {
 	assert.Equal(t, checkSessionNotFound, a.checkSession(sessStr))
 
 	a.Close()
-	os.Remove(fn)
 }
 
 // implements http.ResponseWriter

internal/home/middlewares_test.go

@@ -42,7 +42,10 @@ func TestLimitRequestBody(t *testing.T) {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			var b []byte
 			b, *err = ioutil.ReadAll(r.Body)
-			w.Write(b)
+			_, werr := w.Write(b)
+			if werr != nil {
+				panic(werr)
+			}
 		})
 	}