fix(versionable)!: wrong derived bounds in the Versionize macro

Over-restrictive derived bounds were in some cases unsatisfiable, making the
`versionize` method uncallable.

BREAKING_CHANGE:
- The `#[versionize(bound = ...)]` attribute is not needed anymore, so it has
been removed.

utils/tfhe-versionable/src/upgrade.rs

@@ -3,6 +3,6 @@
 /// This trait should be implemented for each version of the original type that is not the current
 /// one. The upgrade method is called in chains until we get to the last version of the type.
 pub trait Upgrade<T> {
-    type Error: std::error::Error;
+    type Error: std::error::Error + Send + Sync + 'static;
     fn upgrade(self) -> Result<T, Self::Error>;
 }