Fix serde support for linfa-pls algorithms (#380)

* Fix serde support for `linfa-pls` algorithms

* Relax codecov checking

* Bump MSRV 1.81

* Add derive for Debug, Clone and PartialEq traits

Author: relf

.github/codecov.yml

@@ -0,0 +1,8 @@
+coverage:
+  status:
+    project: 
+      default:
+        threshold: 1%
+    patch:
+      default:
+        informational: true

.github/workflows/testing.yml

@@ -35,7 +35,7 @@ jobs:
       fail-fast: false
       matrix:
         toolchain:
-          - 1.71.1
+          - 1.81.0
           - stable
         os:
           - ubuntu-latest

algorithms/linfa-pls/src/lib.rs

@@ -51,8 +51,17 @@ pub use errors::*;
 pub use hyperparams::*;
 pub use pls_svd::*;
 
+#[cfg(feature = "serde")]
+use serde_crate::{Deserialize, Serialize};
+
 macro_rules! pls_algo { ($name:ident) => {
     paste::item! {
+        #[cfg_attr(
+            feature = "serde",
+            derive(Serialize, Deserialize),
+            serde(crate = "serde_crate")
+        )]
+        #[derive(Debug, Clone, PartialEq)]
         pub struct [<Pls $name>]<F: Float>(Pls<F>);
         impl<F: Float> [<Pls $name>]<F> {