[testnet] Add AssetHubRococo <-> AssetHubWestend asset bridging support (#1967)

## Summary

Asset bridging support for AssetHub**Rococo** <-> AssetHub**Wococo** was
added [here](https://github.com/paritytech/polkadot-sdk/pull/1215), so
now we aim to bridge AssetHub**Rococo** and AssetHub**Westend**. (And
perhaps retire AssetHubWococo and the Wococo chains).

## Solution

**bridge-hub-westend-runtime**
- added new runtime as a copy of `bridge-hub-rococo-runtime`
- added support for bridging to `BridgeHubRococo`
- added tests and benchmarks

**bridge-hub-rococo-runtime**
- added support for bridging to `BridgeHubWestend`
- added tests and benchmarks
- internal refactoring by splitting bridge configuration per network,
e.g., `bridge_to_whatevernetwork_config.rs`.

**asset-hub-rococo-runtime**
- added support for asset bridging to `AssetHubWestend` (allows to
receive only WNDs)
- added new xcm router for `Westend`
- added tests and benchmarks

**asset-hub-westend-runtime**
- added support for asset bridging to `AssetHubRococo` (allows to
receive only ROCs)
- added new xcm router for `Rococo`
- added tests and benchmarks

## Deployment

All changes will be deployed as a part of
https://github.com/paritytech/polkadot-sdk/issues/1988.

## TODO

- [x] benchmarks for all pallet instances
- [x] integration tests
- [x] local run scripts


Relates to:
https://github.com/paritytech/parity-bridges-common/issues/2602
Relates to: https://github.com/paritytech/polkadot-sdk/issues/1988

---------

Co-authored-by: command-bot <>
Co-authored-by: Adrian Catangiu <adrian@parity.io>
Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>

cumulus/parachains/runtimes/assets/asset-hub-westend/Cargo.toml

@@ -71,7 +71,7 @@ cumulus-pallet-dmp-queue = { path = "../../../../pallets/dmp-queue", default-fea
 cumulus-pallet-parachain-system = { path = "../../../../pallets/parachain-system", default-features = false, features = ["parameterized-consensus-hook",] }
 cumulus-pallet-session-benchmarking = { path = "../../../../pallets/session-benchmarking", default-features = false}
 cumulus-pallet-xcm = { path = "../../../../pallets/xcm", default-features = false }
-cumulus-pallet-xcmp-queue = { path = "../../../../pallets/xcmp-queue", default-features = false }
+cumulus-pallet-xcmp-queue = { path = "../../../../pallets/xcmp-queue", default-features = false, features = ["bridging"] }
 cumulus-primitives-core = { path = "../../../../primitives/core", default-features = false }
 cumulus-primitives-utility = { path = "../../../../primitives/utility", default-features = false }
 pallet-collator-selection = { path = "../../../../pallets/collator-selection", default-features = false }
@@ -79,10 +79,15 @@ parachain-info = { package = "staging-parachain-info", path = "../../../pallets/
 parachains-common = { path = "../../../common", default-features = false }
 assets-common = { path = "../common", default-features = false }
 
+# Bridges
+pallet-xcm-bridge-hub-router = { path = "../../../../../bridges/modules/xcm-bridge-hub-router", default-features = false }
+bp-asset-hub-rococo = { path = "../../../../../bridges/primitives/chain-asset-hub-rococo", default-features = false }
+bp-asset-hub-westend = { path = "../../../../../bridges/primitives/chain-asset-hub-westend", default-features = false }
+bp-bridge-hub-westend = { path = "../../../../../bridges/primitives/chain-bridge-hub-westend", default-features = false }
+
 [dev-dependencies]
 hex-literal = "0.4.1"
 asset-test-utils = { path = "../test-utils" }
-sp-io = { path = "../../../../../substrate/primitives/io" }
 
 [build-dependencies]
 substrate-wasm-builder = { path = "../../../../../substrate/utils/wasm-builder", optional = true }
@@ -112,6 +117,7 @@ runtime-benchmarks = [
 	"pallet-uniques/runtime-benchmarks",
 	"pallet-utility/runtime-benchmarks",
 	"pallet-xcm-benchmarks/runtime-benchmarks",
+	"pallet-xcm-bridge-hub-router/runtime-benchmarks",
 	"pallet-xcm/runtime-benchmarks",
 	"parachains-common/runtime-benchmarks",
 	"polkadot-parachain-primitives/runtime-benchmarks",
@@ -146,6 +152,7 @@ try-runtime = [
 	"pallet-transaction-payment/try-runtime",
 	"pallet-uniques/try-runtime",
 	"pallet-utility/try-runtime",
+	"pallet-xcm-bridge-hub-router/try-runtime",
 	"pallet-xcm/try-runtime",
 	"parachain-info/try-runtime",
 	"polkadot-runtime-common/try-runtime",
@@ -153,6 +160,9 @@ try-runtime = [
 ]
 std = [
 	"assets-common/std",
+	"bp-asset-hub-rococo/std",
+	"bp-asset-hub-westend/std",
+	"bp-bridge-hub-westend/std",
 	"codec/std",
 	"cumulus-pallet-aura-ext/std",
 	"cumulus-pallet-dmp-queue/std",
@@ -189,6 +199,7 @@ std = [
 	"pallet-uniques/std",
 	"pallet-utility/std",
 	"pallet-xcm-benchmarks?/std",
+	"pallet-xcm-bridge-hub-router/std",
 	"pallet-xcm/std",
 	"parachain-info/std",
 	"parachains-common/std",