feat(spans): Remove group_raw from the schema as it's not used anymore

[phacops]

No description provided.

[github-actions]

versions in use:

The following repositories use one of the schemas you are editing. It is recommended to roll out schema changes in small PRs, meaning that if those used versions lag behind the latest, it is probably best to update those services before rolling out your change.

• getsentry/sentry: pip:sentry-kafka-schemas==0.1.38 (upgrade)
• getsentry/snuba: pip:sentry-kafka-schemas==0.1.38 (upgrade)
• getsentry/snuba: rust:sentry-kafka-schemas==0.1.40

latest version: 0.1.40

benign changes

schemas/snuba-spans.v1.schema.json

• Removed a property group_raw from ``, but it is still accepted via additionalProperties=true

  {"path": "", "change": {"PropertyRemove": {"lhs_additional_properties": true, "removed": "group_raw"}}}
  

✅ This PR should be safe to roll out to consumers first. Make sure to bump
the library in the following repos first:

getsentry/snuba

...then in the other repos:

getsentry/sentry

Take a look at the README for how to release a new version of sentry-kafka-schemas.