fixup serde feature

klondike/Cargo.toml

@@ -19,4 +19,4 @@ workspace = true
 
 [features]
 default = ["serde"]
-serde = ["dep:serde", "dep:serde_derive"]
+serde = ["dep:serde", "dep:serde_derive", "card_game/serde"]

klondike/src/test.rs

@@ -17,6 +17,7 @@ fn test_is_winnable() {
 }
 
 
+#[cfg(feature = "serde")]
 #[test]
 fn test_json() {
 	let mut session = Session::new_default(Klondike::with_seed(124));
@@ -33,6 +34,7 @@ fn test_json() {
 	assert_eq!(serialized, serialized2);
 }
 
+#[cfg(feature = "serde")]
 #[test]
 fn test_rmp() {
 	let mut session = Session::new_default(Klondike::with_seed(124));