Metadata is not set in Cap, which is required by the inherited Router to specify gas limit to the mailbox

Description

The gas limit of messages must be set in the metadata function, as indicated by the docs.

When it is not set, the gas limit defaults to 50_000, which may not be enough to handle the epoch increase on the destination.

Recommendation

Overwrite the function with the correct metadata. Additionally, the Hyperlane version used is old, consider using a more recent one. In the newer version, metadata is sent as an argument, which makes it more obvious that it must be set.

Status

Addressed in #669b422.