Move PalletVersion away from the crate version (#9165)

* Move `PalletVersion` away from the crate version

Before this pr, `PalletVersion` was referring to the crate version that
hosted the pallet. This pr introduces a custom `package.metadata.frame`
section in the `Cargo.toml` that can contain a `pallet-version` key
value pair. While the value is expected to be a valid u16. If this
key/value pair isn't given, the version is set to 1.

It also changes the `PalletVersion` declaration. We now only have one
`u16` that represents the version. Not a major/minor/patch version. As
the old `PalletVersion` was starting with the `u16` major, decoding the
old values will work.

* Overhaul the entire implementation

- Drop PalletVersion
- Introduce StorageVersion
- StorageVersion needs to be set in the crate and set for the macros
- Added migration

* Fix migrations

* Review feedback

* Remove unneeded dep

* remove pub consts

* Brings back logging and implements `GetStorageVersion`

* Return weight from migration

* Fmt and remove unused import

* Update frame/support/src/dispatch.rs

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

* Update frame/support/src/traits/metadata.rs

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

substrate/frame/support/test/src/lib.rs

@@ -22,9 +22,6 @@
 #![warn(missing_docs)]
 #![deny(warnings)]
 
-#[cfg(test)]
-mod pallet_version;
-
 /// The configuration trait
 pub trait Config: 'static {
 	/// The runtime origin type.