remove conflicting default impl

src/parser.rs

@@ -50,6 +50,7 @@ impl ConfigField {
                             derive.contains("Tree")
                                 || derive.contains("Serialize")
                                 || derive.contains("Deserialize")
+                                || (self.default.is_some() && derive.contains("Default"))
                         }) == Some(false)
                     });
                     quote! {#[derive(#(#derives,)*)]}

tests/simple.rs

@@ -31,6 +31,14 @@ struct Config {
     sub_config: SubConfig,
 }
 
+/// Config with default derive and default field
+#[config]
+#[derive(Default)]
+struct _DefaultConfig {
+    #[config(default)]
+    field: i32,
+}
+
 #[rstest]
 #[case(0, ["skipped"])]
 #[case(1, ["min"])]