Improve VersionedMigration naming conventions (paritytech#2264)

As suggested by @ggwpez
(paritytech#2142 (comment)),
remove the `VersionChecked` prefix from version checked migrations (but
leave `VersionUnchecked` prefixes)

---------

Co-authored-by: command-bot <>

substrate/frame/society/src/migrations.rs

@@ -95,14 +95,13 @@ impl<
 
 /// [`VersionUncheckedMigrateToV2`] wrapped in a [`frame_support::migrations::VersionedMigration`],
 /// ensuring the migration is only performed when on-chain version is 0.
-pub type VersionCheckedMigrateToV2<T, I, PastPayouts> =
-	frame_support::migrations::VersionedMigration<
-		0,
-		2,
-		VersionUncheckedMigrateToV2<T, I, PastPayouts>,
-		crate::pallet::Pallet<T, I>,
-		<T as frame_system::Config>::DbWeight,
-	>;
+pub type MigrateToV2<T, I, PastPayouts> = frame_support::migrations::VersionedMigration<
+	0,
+	2,
+	VersionUncheckedMigrateToV2<T, I, PastPayouts>,
+	crate::pallet::Pallet<T, I>,
+	<T as frame_system::Config>::DbWeight,
+>;
 
 pub(crate) mod old {
 	use super::*;

substrate/frame/support/src/migrations.rs

@@ -51,7 +51,7 @@ use sp_std::marker::PhantomData;
 /// 	// OnRuntimeUpgrade implementation...
 /// }
 ///
-/// pub type VersionCheckedMigrateV5ToV6<T, I> =
+/// pub type MigrateV5ToV6<T, I> =
 /// 	VersionedMigration<
 /// 		5,
 /// 		6,
@@ -63,7 +63,7 @@ use sp_std::marker::PhantomData;
 /// // Migrations tuple to pass to the Executive pallet:
 /// pub type Migrations = (
 /// 	// other migrations...
-/// 	VersionCheckedMigrateV5ToV6<T, ()>,
+/// 	MigrateV5ToV6<T, ()>,
 /// 	// other migrations...
 /// );
 /// ```