Increase mainnet spec version

Author: José Molina

runtime/mainnet/src/lib.rs

@@ -226,7 +226,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	spec_name: create_runtime_str!("mythos"),
 	impl_name: create_runtime_str!("mythos"),
 	authoring_version: 1,
-	spec_version: 1011,
+	spec_version: 1012,
 	impl_version: 0,
 	apis: RUNTIME_API_VERSIONS,
 	transaction_version: 1,