[semconv] Badges aren't being displayed properly

[chalin]

Badges (which are inline images) are not being rendered correctly (they would technically need to be marked .img-initial). For context, see open-telemetry/semantic-conventions#2970 (comment), or just see the badge images in https://opentelemetry.io/docs/specs/semconv/registry/entities/browser/, for example.

See also:

• [chore] Clean up Entity snippets - make sure they include identifying vs. descriptive roles semantic-conventions#2970 (comment)