happa release v1.57.3

Jan 26, 2023 Developer Portal happa v1.57.3

Changes

Remove hiring banner by @marians in https://github.com/giantswarm/happa/pull/4026
Internal changes towards supporting cluster creation via app bundles by @kuosandys and @gusevda in https://github.com/giantswarm/happa/pull/3927

Full Changelog: https://github.com/giantswarm/happa/compare/v1.57.2...v1.57.3