fix: adjust migration 0005 to not do a drop table and instead rename …

…delegations -> delegations_old and create a new delegations (#468)

Note:
* this is just for consideration because @Gozala and I are both curious
whether cloudflare migrations will allow the rename. It would be good to
know.
* But i actually think it would probably be best to use
#469 over time

Motivation:
* try out something @Gozala and I came up with for
#464

packages/access-api/migrations/0005_drop_delegations_audience_to_accounts_did_fk.sql

@@ -26,5 +26,5 @@ CREATE TABLE
 INSERT INTO delegations_new (cid, bytes, audience, issuer, expiration, inserted_at, updated_at)
 SELECT cid, bytes, audience, issuer, expiration, inserted_at, updated_at FROM delegations;
 
-DROP TABLE delegations;
+ALTER TABLE delegations RENAME TO delegations_1677808856;
 ALTER TABLE delegations_new RENAME TO delegations;