ref(span-buffer): Update codeowners (#92102)

This is defacto something the streaming platform is working on right
now. If it gets too noisy for some teams we will have to restructure the
code

Author: untitaker

.github/CODEOWNERS

@@ -242,9 +242,6 @@ yarn.lock                                                @getsentry/owners-js-de
 /tests/snuba/api/endpoints/test_organization_events_vitals.py               @getsentry/visibility
 /tests/snuba/api/endpoints/test_organization_tagkey_values.py               @getsentry/visibility
 
-/src/sentry/spans/                                                          @getsentry/visibility
-/tests/sentry/spans/                                                        @getsentry/visibility
-
 /src/sentry/api/serializers/snuba.py                                        @getsentry/visibility
 
 /src/sentry/snuba/discover.py                                               @getsentry/visibility
@@ -673,6 +670,10 @@ tests/sentry/api/endpoints/test_organization_dashboard_widget_details.py     @ge
 /src/sentry/tempest/                                       @getsentry/gdx
 /tests/sentry/tempest/                                     @getsentry/gdx
 
+# Span buffer + process-segments are co-owned by streaming platform and vis for now.
+/src/sentry/spans/                                @getsentry/visibility @getsentry/streaming-platform
+/tests/sentry/spans/                              @getsentry/visibility @getsentry/streaming-platform
+
 # Workflow engine
 /src/sentry/workflow_engine/                               @getsentry/alerts-create-issues
 /tests/sentry/workflow_engine/                             @getsentry/alerts-create-issues