feat(http/body-eos): EosRef<'a, E> is clonable

Signed-off-by: katelyn martin <[email protected]>

Author: cratelyn

linkerd/http/body-eos/src/lib.rs

@@ -130,3 +130,21 @@ where
         };
     }
 }
+
+// === impl EosRef ===
+
+/// A reference to the end of a stream can be cheaply cloned.
+///
+/// Each of the variants are empty tags, or immutable references.
+impl<'a, E> Clone for EosRef<'a, E> {
+    fn clone(&self) -> Self {
+        match self {
+            Self::None => Self::None,
+            Self::Cancelled => Self::Cancelled,
+            Self::Trailers(trls) => Self::Trailers(trls),
+            Self::Error(err) => Self::Error(err),
+        }
+    }
+}
+
+impl<'a, E> Copy for EosRef<'a, E> {}