Deprecate scheduler traits v1 and v2 (#3718)

This PR add `#[deprecated]` attribute to v1 and v2 of the schedule
trait. Proposed in this issue:
https://github.com/paritytech/polkadot-sdk/issues/3676

```rust
#[allow(deprecated)]
#[deprecated = "traits::schedule::v1 is deprecated. Please use v3 instead."]
pub mod v1 {
...
}

#[allow(deprecated)]
#[deprecated = "traits::schedule::v2 is deprecated. Please use v3 instead."]
pub mod v2 {
...
}
```

polkadot address: 19nSqFQorfF2HxD3oBzWM3oCh4SaCRKWt1yvmgaPYGCo71J

---------

Co-authored-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Liam Aharon <[email protected]>