Bluesky: refresh DID doc when user follows ap.brid.gy

[snarfed]

Evidently we're not refreshing a user's DID doc when they first follow ap.brid.gy, which means we occasionally have a stale wrong handle.

Example: did:plc:usl4pnhyasr2moto7elbvhw6 . Changed their handle from cyrneko.codeberg.page to cyrneko.eu at 2024-09-14 12:59 PM PT, then followed ap.brid.gy at 2024-09-15 18:31:06 PT. We already had their DID doc from beforehand, with cyrneko.codeberg.page, and we didn't reload it, so we bridged them with that handle.

Related: #1017, #1201

[danielledeleo]

Seeing this for my account (should be @transpile.net, but it got picked up as @caffein.ated.io)

[snarfed]

@danielledeleo sorry for the trouble! I've refreshed your DID doc, feel free to try again.