feat(config): allow printing default and computed config (#2521)

* feat: allow printing default and computed config

* fix custom modules

* actually fix custom modules

src/configs/starship_root.rs

@@ -1,8 +1,9 @@
 use crate::config::ModuleConfig;
 
+use serde::Serialize;
 use starship_module_config_derive::ModuleConfig;
 
-#[derive(Clone, ModuleConfig)]
+#[derive(Clone, ModuleConfig, Serialize)]
 pub struct StarshipRootConfig<'a> {
     pub format: &'a str,
     pub scan_timeout: u64,