public async Task RequestsCorrectUrl()
        {
            var connection = Substitute.For<IApiConnection>();
            var client = new RepositoryInvitationsClient(connection);
            var updatedInvitation = new InvitationUpdate(InvitationPermissionType.Read);

            await client.Edit(1, 2, updatedInvitation);

            connection.Received().Patch<RepositoryInvitation>(Arg.Is<Uri>(u => u.ToString() == "repositories/1/invitations/2"), Arg.Is<InvitationUpdate>(updatedInvitation), "application/vnd.github.swamp-thing-preview+json");
        }
        public async Task EnsureNonNullArguments()
        {
            var client = new RepositoryInvitationsClient(Substitute.For<IApiConnection>());

            await Assert.ThrowsAsync<ArgumentNullException>(() => client.Edit(1, 2, null));
        }