test(acl): diploma document sets indicatiegebruiksrecht so the zaak can close (refs #103)

The behandelaar approval closes the zaak via OpenZaak. A related
informatieobject with indicatieGebruiksrecht left null makes OpenZaak
reject the close (400 indicatiegebruiksrecht-unset), surfacing as a 500
and failing the registration e2e flow.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

services/acl/Acl.Tests/OpenZaakGatewayTests.cs

@@ -489,6 +489,9 @@ public class OpenZaakGatewayTests
         Assert.Contains("\"formaat\":\"application/pdf\"", create.Body);
         Assert.Contains("\"vertrouwelijkheidaanduiding\":\"openbaar\"", create.Body);
         Assert.Contains("\"status\":\"definitief\"", create.Body);
+        // indicatieGebruiksrecht must be set explicitly (false = no usage restrictions); left null,
+        // OpenZaak refuses to close the zaak this document is related to ("indicatiegebruiksrecht-unset").
+        Assert.Contains("\"indicatiegebruiksrecht\":false", create.Body);
         // The file content is base64-encoded into `inhoud`, with its byte length in `bestandsomvang`.
         Assert.Contains($"\"inhoud\":\"{Convert.ToBase64String([10, 20, 30])}\"", create.Body);
         Assert.Contains("\"bestandsomvang\":3", create.Body);