Add a component level tests for the transition out of Conway era

[dnadales]

We need to test a successful transition from Conway to the next era (Dijkstra at the moment of writing this issue).

This depends on #920

[dnadales]

See also #542

[amesgen]

We are pausing this until there is an era after Conway, as that is the point in time where testing this actually gets important.

Before that, testing this it is a bit annoying (but not impossible), as we would have to "fake" a post-Conway era (the easiest way would be to add Conway again to the list passed to HardForkBlock, but it will still be quite a lot of ceremony for what it is accomplishing.).

[amesgen]

Dijkstra has been integrated: #1567