Updated endpoints.json.

Author: AWS

.changes/next-release/feature-AWSSDKforJavav2-bedacd4.json

@@ -0,0 +1,6 @@
+{
+    "type": "feature",
+    "category": "AWS SDK for Java v2",
+    "contributor": "",
+    "description": "Updated service endpoint metadata."
+}

core/regions/src/main/resources/software/amazon/awssdk/regions/internal/region/endpoints.json

@@ -15933,7 +15933,12 @@
       },
       "portal.sso" : {
         "endpoints" : {
-          "us-gov-east-1" : { },
+          "us-gov-east-1" : {
+            "credentialScope" : {
+              "region" : "us-gov-east-1"
+            },
+            "hostname" : "portal.sso.us-gov-east-1.amazonaws.com"
+          },
           "us-gov-west-1" : {
             "credentialScope" : {
               "region" : "us-gov-west-1"