We want to allow additional Hako environments in the future,
particularly because some apps will be deployed to their own
environments. We still need to assume some standardised structure,
however, so that we can infer the domain and region from their name.

This allows flexibility for when apps want to deploy to custom
environments.

We drop the old `multiregion` option as part of this change as it can
now be better expressed by setting the `hakoProductionEnvironments`
option, rather than carving out a special case for the ft-com
environments. We could have preserved backwards-compatibility with this
change – or even continued supporting the option – but it feels better
to rip the bandage off now whilst not many apps have it set and to
encourage one way of defining multiple environments.

This is such a simple dependency that it makes sense to pin it to
minimise our supply chain attack surface. Let's do the same for the
monorepo package version too.

Co-Authored-By: Olusola Oguntimehin <[email protected]>

This issue was highlighted when I imported a bad path in a schema
entrypoint and the only error I got was that the options were bad in the
given plugin but then 0 errors were reported from that plugin... Not
helpful!