[Feed health] Community Builders Community Events: feed unreachable or invalid

[github-actions]

The feed of Community Builders Community Events has failed its daily health check 3 times in a row (since 2026-08-28).

• Feed: https://communitybuilders.dev/events/feed.json
• Website: https://communitybuilders.dev/#events
• Last error:

schema errors:
data/specVersion must be equal to constant

If the feed is gone for good, delist the community with a PR removing its entry from docs/data/adopters.json. If it's temporary, this issue closes itself when the feed recovers.

[hhkaos]

False positive: the feed answers 200 and validates against 0.4. It takes ~51s to serve 551 KB and the check aborted at 20s.

Fixed in #43: 60s timeout, 3 attempts with backoff, and timeouts/5xx now need 5 of the last 7 daily runs before an issue opens.