Remove the local `RELEASE_CHANNEL` source that seems to be used only for Linux as opposed to `channel_release::CHANNEL_RELEASE_NAME` for other platform Windows: https://github.com/zed-industries/zed/blob/eee1b1f8a8ba47a14efc524a21b63d896b03feff/crates/cli/src/main.rs#L681-L685 Release Notes: - N/A