fixed struct alignment && refactor linter (#369)

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Reviewed-on: #369
Co-authored-by: Evstigneev Denis <danteevstigneev@yandex.ru>
Co-committed-by: Evstigneev Denis <danteevstigneev@yandex.ru>

util/dns/cache_test.go

@@ -8,15 +8,13 @@ import (
 func TestCache(t *testing.T) {
 	net.DefaultResolver = NewNetResolver(PreferIPV4(true))
 
-	addrs, err := net.LookupHost("unistack.org")
+	_, err := net.LookupHost("unistack.org")
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	addrs, err = net.LookupHost("unistack.org")
+	_, err = net.LookupHost("unistack.org")
 	if err != nil {
 		t.Fatal(err)
 	}
-
-	_ = addrs
 }