Fix broken documentation in Connectivity

EthernetManager is @SystemApi, so cannot be referenced from public
API.

Bug: 303184203
Test: m docs
Change-Id: Ib5cc07c89b4ecfdeae704da131ebb307816e35fa
diff --git a/framework-t/src/android/net/EthernetNetworkSpecifier.java b/framework-t/src/android/net/EthernetNetworkSpecifier.java
index e4d6e24..90c0361 100644
--- a/framework-t/src/android/net/EthernetNetworkSpecifier.java
+++ b/framework-t/src/android/net/EthernetNetworkSpecifier.java
@@ -26,8 +26,6 @@
 
 /**
  * A {@link NetworkSpecifier} used to identify ethernet interfaces.
- *
- * @see EthernetManager
  */
 public final class EthernetNetworkSpecifier extends NetworkSpecifier implements Parcelable {