release notes for 1.8.1 (#8639)

* release notes for 1.8.1

* Update content/en/news/releases/1.8.x/announcing-1.8.1/index.md

Co-authored-by: Eric Van Norman <ericvn@us.ibm.com>

* wording fix

Co-authored-by: Eric Van Norman <ericvn@us.ibm.com>

content/en/news/releases/1.8.x/announcing-1.8.1/index.md

@@ -0,0 +1,28 @@
+---
+title: Announcing Istio 1.8.1
+linktitle: 1.8.1
+subtitle: Patch Release
+description: Istio 1.8.1 patch release.
+publishdate: 2020-12-08
+release: 1.8.1
+aliases:
+    - /news/announcing-1.8.1
+---
+
+This release contains bug fixes to improve robustness. This release note describes what’s different between Istio 1.8.0 and Istio 1.8.1
+
+{{< relnote >}}
+
+## Changes
+
+- **Fixed** an issue showing unnecessary warnings when downgrading to a lower version of Istio.
+  ([Issue #29183](https://github.com/istio/istio/issues/29183))
+
+- **Fixed** an issue where a delegate `VirtualService` change would not trigger an xDS push.
+  ([Issue #29123](https://github.com/istio/istio/issues/29123))
+
+- **Fixed** a regression in Istio 1.8.0 causing workloads with multiple Services with overlapping ports to send
+traffic to the wrong port.
+  ([Issue #29199](https://github.com/istio/istio/issues/29199))
+
+- **Fixed** a bug causing Istio to attempt to validate resource types it no longer supports.