Fix eds cluster loadassignment with invalid endpoint (#50690)

* fix eds cluster has invalid endpoints

* Add release note

* Fix specical case ep address empty

* add uds addr check

* use IsValidIP

pilot/pkg/xds/endpoints/ep_filters_test.go

@@ -834,6 +834,7 @@ func testShards() *model.EndpointIndex {
 		// network1 has one endpoint in each cluster
 		{Cluster: "cluster1a"}: {
 			{Network: "network1", Address: "10.0.0.1"},
+			{Network: "network1", Address: "foo.bar"}, // endpoint generated from ServiceEntry
 		},
 		{Cluster: "cluster1b"}: {
 			{Network: "network1", Address: "10.0.0.2"},

releasenotes/notes/50688.yaml

@@ -0,0 +1,8 @@
+apiVersion: release-notes/v2
+kind: bug-fix
+area: traffic-management
+issue:
+  - 50688
+releaseNotes:
+- |
+  **Fixed** build EDS typed cluster endpoints with domain address.