vauilwarden: build webvault explicitly on hydra to better notice when… (#482852)

  vaultwarden-sqlite = vaultwarden;

  vaultwarden-mysql = vaultwarden.override { dbBackend = "mysql"; };

  vaultwarden-postgresql = vaultwarden.override { dbBackend = "postgresql"; };

  vaultwarden-webvault = vaultwarden.webvault;

  vimUtils = callPackage ../applications/editors/vim/plugins/utils/vim-utils.nix { };