The {% amendments-table /%} and {% amendment-disclaimer /%} components call https://vhs.prod.ripplex.io/v1/network/amendments/vote/main/ to get amendment status data—but if you include multiples of them in a page, it calls that API multiple times per page load.

We should cache that data since it doesn't need to be redundantly fetched and refreshed. (At maximum, the ledger's amendment status can only change about every 15 minutes.) It would also be nice to refactor the two components to share some code for fetching the data as well.

(Continues from #3227 and #3219.)