Update CHANGELOG.md

Author: morgante

CHANGELOG.md

@@ -122,7 +122,7 @@ and this project adheres to [Semantic Versioning][semver-site].
 - Subnets within the VPC
 - Secondary ranges for the subnets (if applicable)
 
-[Unreleased]: https://github.com/terraform-google-modules/terraform-google-network/compare/v1.3.0...HEAD
+[Unreleased]: https://github.com/terraform-google-modules/terraform-google-network/compare/v1.4.0...HEAD
 [1.4.0]: https://github.com/terraform-google-modules/terraform-google-network/compare/v1.3.0...v1.4.0
 [1.3.0]: https://github.com/terraform-google-modules/terraform-google-network/compare/v1.2.0...v1.3.0
 [1.2.0]: https://github.com/terraform-google-modules/terraform-google-network/compare/v1.1.0...v1.2.0