warg-server Args no-such-field without postgres feature

[kriswuollett]

Visual Studio Code displays no such fieldrust-analyzer[no-such-field](https://rust-analyzer.github.io/manual.html#no-such-field) on the following when feature postgres is not included in analyzer settings:

registry/crates/server/src/bin/warg-server.rs

Line 17 in 72a9049

#[derive(Parser, Debug)]

{
    // "rust-analyzer.cargo.features": ["postgres"],
}

The error goes away when the database_url and database_url_file fields are commented out:

registry/crates/server/src/bin/warg-server.rs

Lines 35 to 48 in 72a9049

	/// The database connection URL if data-store is set to postgres.
	///
	/// Prefer using database-url-file, or environment variable variation,
	/// to avoid exposing sensitive information.
	#[cfg(feature = "postgres")]
	#[arg(long, env = "DATABASE_URL")]
	database_url: Option<String>,
	/// The path to the operator key.
	///
	/// Takes precedence over database-url.
	#[cfg(feature = "postgres")]
	#[arg(long, env = "DATABASE_URL_FILE")]
	database_url_file: Option<PathBuf>,

[kriswuollett]

Perhaps another false positive like rust-lang/rust-analyzer#11473

[peterhuene]

Merged the workaround, so I think we can close this for now.