Update CHANGELOG.md (#154)

Author: mohammadualam

charts/sourcegraph/CHANGELOG.md

@@ -10,6 +10,12 @@ Use `**BREAKING**:` to denote a breaking change
 
 ### Added
 
+
+
+## 3.42.0
+
+Sourcegraph 3.42.0 is now available!
+
 - Add new example `envoy` to enable HTTP trailers using Envoy Filter [#148](https://github.com/sourcegraph/deploy-sourcegraph-helm/pull/148)
 - Add support to configure service account annotations [#151](https://github.com/sourcegraph/deploy-sourcegraph-helm/pull/151)