[MM-62412] Block login of SAML users if no connected LDAP user is found (#29786)

server/i18n/en.json

@@ -8364,6 +8364,10 @@
     "id": "ent.saml.license_disable.app_error",
     "translation": "Your license does not support SAML authentication."
   },
+  {
+    "id": "ent.saml.login.ldap_user_missing",
+    "translation": "No user registered on AD/LDAP server that matches the SAML user."
+  },
   {
     "id": "ent.saml.metadata.app_error",
     "translation": "An error occurred while building Service Provider Metadata."