Registry data cleanup: update entries to eliminate warnings

[chalin]

Originally posted by @chalin in #5597 (comment):

@svrnm - we should do something about incrementally eliminating the registry warnings.

Related:

• Move integrations to registry #4991
• Blame page, to see who added integration entries to the original integrations file:
  • https://github.com/open-telemetry/opentelemetry.io/blame/30783526402b69a3ac44eeb0f6cf066732f0bdca/data/ecosystem/integrations.yaml
• Registry URL validation doesn't match template guidance #5511

Tasks

• Update entries to eliminate warnings
  Registry: add missing URL for Traefik #5602
• Enable CI check so that issues are caught when PRs are submitted