mozillavpn: Disable debug mode
mozillavpn: Disable debug mode

Upstream uses a broken test for debug mode, so we need to redundantly
disable debug even though we already enable release:

https://github.com/mozilla-mobile/mozilla-vpn-client/pull/3539

Signed-off-by: Anders Kaseorg <087231934ba8fcf78bc142ce37d193b895ac03c4@mit.edu>

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs