Update pubspec/changelog for sass/embedded-host-node#399 (#2682)

See sass/embedded-host-node#398

Author: nex3

CHANGELOG.md

@@ -8,6 +8,11 @@
 * `Deprecation.forVersion` now excludes obsolete deprecations from the set it
   returns.
 
+### Node.js Embedded Host
+
+* Fix a bug where a variable could be used before it was initialized during
+  async compilation.
+
 ## 1.94.1
 
 * No user-visible changes.