### Description

In [TransportSamlInitiateSingleSignOnActionTests.java](https://github.com/elastic/elasticsearch/pull/98882/files#diff-26733d11b06442213a040cc3d5c89595300ec813bb31076874afa38ef2ad3b91),  `/api/security/v1/saml` (deprecated) should be replaced with /api/security/saml/callback

In https://github.com/elastic/kibana/blob/b33effa182bcb7c9620c5435ab252d8067732655/x-pack/plugins/security/server/routes/authentication/saml.ts#L27

/api/security/saml/callback is the correct URL,
while /api/security/v1/saml is the deprecated URL.

Related to https://github.com/elastic/cloud-on-k8s/issues/7118
x-pack/plugin/identity-provider/src/test/java/org/elasticsearch/xpack/idp/action/TransportSamlInitiateSingleSignOnActionTests.java
action.doExecute(mock(Task.class), request, future);
        final SamlInitiateSingleSignOnResponse response = future.get();
        assertThat(response.getError(), equalTo("Request is missing secondary authentication"));
        assertThat(response.getSamlStatus(), equalTo(StatusCode.REQUESTER));
        assertThat(response.getPostUrl(), equalTo("https://sp.some.org/saml/acs"));
        assertThat(response.getEntityId(), equalTo("https://sp.some.org"));
        assertThat(response.getSamlResponse(), containsString("InResponseTo=\"" + requestId + "\""));
    }
    @SuppressWarnings("unchecked")
    private TransportSamlInitiateSingleSignOnAction setupTransportAction(boolean withSecondaryAuth) throws Exception {
        final Settings settings = Settings.builder()
            .put("path.home", createTempDir())
            .put("xpack.idp.enabled", true)
            .put("xpack.idp.entity_id", "https://idp.cloud.elastic.co")
            .put("xpack.idp.sso_endpoint.redirect", "https://idp.cloud.elastic.co/saml/init")
            .put("xpack.idp.organization.url", "https://cloud.elastic.co")
            .put("xpack.idp.organization.name", "Cloud Elastic")
            .put("xpack.idp.contact.email", "some@other.org")
            .build();
        final ThreadContext threadContext = new ThreadContext(settings);
        final ThreadPool threadPool = mock(ThreadPool.class);
        final SecurityContext securityContext = new SecurityContext(settings, threadContext);
        final TransportService transportService = new TransportService(
            Settings.EMPTY,
            mock(Transport.class),
            threadPool,
            TransportService.NOOP_TRANSPORT_INTERCEPTOR,
            x -> null,
            null,
            Collections.emptySet()