Add release notes for 1.10.3 (#10059)

* Add release notes for 1.10.3

* Fix spelling

* Add trailing period

* Update date

.spelling

@@ -584,6 +584,7 @@ operationalize
 OS-level
 Ostrowski
 outsized
+overridden
 p50
 p99
 PaaS

content/en/news/releases/1.10.x/announcing-1.10.3/index.md

@@ -0,0 +1,23 @@
+---
+title: Announcing Istio 1.10.3
+linktitle: 1.10.3
+subtitle: Patch Release
+description: Istio 1.10.3 patch release.
+publishdate: 2021-07-16
+release: 1.10.3
+aliases:
+    - /news/announcing-1.10.3
+---
+
+This release contains bug fixes to improve robustness. This release note describes what’s different between Istio 1.10.2 and Istio 1.10.3.
+
+{{< relnote >}}
+
+## Changes
+
+- **Fixed** a bug where wildcard hosts were incorrectly added even when a `Sidecar` resource only specified particular hosts.  ([Issue #33387](https://github.com/istio/istio/issues/33387))
+
+- **Fixed** a bug where setting the `retryRemoteLocalities` on a `VirtualService` would produce configuration that Envoy would reject.  ([Issue #33737](https://github.com/istio/istio/issues/33737))
+
+- **Improved** the `meshConfig.defaultConfig.proxyMetadata` field to do a deep merge when overridden rather than replacing all values.
+