add missing item

Author: chrisbreiding

content/_changelogs/10.9.0.md

@@ -22,6 +22,11 @@ _Released 9/27/2022_
 - Added support for advanced dev server configuration via an async function that
   can optionally modify the dev server config. Addresses
   [#23302](https://github.com/cypress-io/cypress/issues/23302).
+- Launch options returned from the
+  [`before:browser:launch`](/api/plugins/browser-launch-api) event can now
+  include an `env` key that can be used to pass environment variables to the
+  browser when it is launched. Addressed by
+  [#23624](https://github.com/cypress-io/cypress/pull/23624).
 
 **Bugfixes:**