Sibling Fellowship Referendum: https://collectives.subsquare.io/fellowship/referendum/0

As explained in the Fellowship referendum description, the v9420 runtime upgrade did not enact successfully on the Bridge Hub because the Relay Chain's XCM version was too old. This proposal corrects the error from [Gov1 Ref 121](https://polkadot.subsquare.io/democracy/referendum/121) did for the Bridge Hub. All other calls within 121 worked as planned, only the Bridge Hub was affected.

- Problem Statement: Addressing the failed v9420 runtime upgrade on the Bridge Hub due to an outdated XCM version.
- Significance: Correcting the error from a previous referendum (Gov1 Ref 121) to ensure the Bridge Hub functions properly.
- Proposed Solution: Implementing necessary updates to the Bridge Hub to enable the successful v9420 runtime upgrade.
- Expected Outcomes: Ensuring the Bridge Hub operates effectively post-upgrade, avoiding future disruptions.

#3 [Whitelisted Caller] Referendum #3: Upgrade Bridge Hub to v9420