### 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
);
        final ActionFilters actionFilters = mock(ActionFilters.class);
        final Environment env = TestEnvironment.newEnvironment(settings);
        when(threadPool.getThreadContext()).thenReturn(threadContext);
        AuthenticationTestHelper.builder()
            .user(new User("not-saml_service_account", "not-saml_service_role"))
            .realmRef(new Authentication.RealmRef("default_native", "native", "node_name"))
            .runAs()
            .user(new User("saml_service_account", "saml_service_role"))
            .realmRef(new Authentication.RealmRef("default_native", "native", "node_name"))
            .build()
            .writeToContext(threadContext);
        if (withSecondaryAuth) {
            new SecondaryAuthentication(
                securityContext,
                AuthenticationTestHelper.builder()
                    .apiKey()
                    .user(
                        new User(
                            "saml_enduser",
                            new String[] { "saml_enduser_role" },
                            "Saml Enduser",
                            "samlenduser@elastic.co",
                            new HashMap<>(),
                            true
                        )
                    )
                    .build()
            ).writeToContext(threadContext);
        }