Hydroconf.discover_sources() seems not to respect HydroSettings.settings_file

[hongquan]

When looking into HydroSettings, I thought that the settings_file field is to guide Hydroconf to look into right source file. But when reading Hydroconf.discover_sources() implementation, it seems not to. It only takes HydroSettings.env into account.

pub fn discover_sources(&mut self) {
    self.sources = self
        .root_path()
        .map(|p| {
            FileSources::from_root(p, self.hydro_settings.env.as_str())
        })
        .unwrap_or_else(|| FileSources::default());
}