Adds Snowbridge to Rococo runtime (#2522)

# Description

Adds Snowbridge to the Rococo bridge hub runtime. Includes config
changes required in Rococo asset hub.

---------

Co-authored-by: Alistair Singh <alistair.singh7@gmail.com>
Co-authored-by: ron <yrong1997@gmail.com>
Co-authored-by: Vincent Geddes <vincent.geddes@hey.com>
Co-authored-by: claravanstaden <Cats 4 life!>

bridges/snowbridge/parachain/pallets/system/src/api.rs

@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: 2023 Snowfork <hello@snowfork.com>
+//! Helpers for implementing runtime api
+
+use snowbridge_core::AgentId;
+use xcm::{prelude::*, VersionedMultiLocation};
+
+use crate::{agent_id_of, Config};
+
+pub fn agent_id<Runtime>(location: VersionedMultiLocation) -> Option<AgentId>
+where
+	Runtime: Config,
+{
+	let location: MultiLocation = location.try_into().ok()?;
+	agent_id_of::<Runtime>(&location).ok()
+}