Codeowners: Make Grafana Frontend Platform only own Grafana UI documentation (#100314)

* Codeowners: Make Grafana Frontend Platform exclusive owners of MDX documentation

* more

.github/CODEOWNERS

@@ -405,7 +405,7 @@
 /packages/grafana-schema/src/**/*canvas* @grafana/dataviz-squad
 /packages/grafana-schema/src/**/*tempo* @grafana/observability-traces-and-profiling
 /packages/grafana-sql/ @grafana/partner-datasources @grafana/oss-big-tent
-/packages/grafana-ui/.storybook/ @grafana/plugins-platform-frontend
+/packages/grafana-ui/.storybook/ @grafana/grafana-frontend-platform
 /packages/grafana-ui/src/components/ @grafana/grafana-frontend-platform
 /packages/grafana-ui/src/components/BarGauge/ @grafana/dataviz-squad
 /packages/grafana-ui/src/components/DataLinks/ @grafana/dataviz-squad
@@ -424,7 +424,7 @@
 /packages/grafana-ui/src/graveyard/Graph/ @grafana/dataviz-squad
 /packages/grafana-ui/src/graveyard/GraphNG/ @grafana/dataviz-squad
 /packages/grafana-ui/src/graveyard/TimeSeries/ @grafana/dataviz-squad
-/packages/grafana-ui/src/utils/storybook/ @grafana/plugins-platform-frontend
+/packages/grafana-ui/src/utils/storybook/ @grafana/grafana-frontend-platform
 
 # root files, mostly frontend
 /.browserslistrc @grafana/frontend-ops
@@ -637,9 +637,6 @@ playwright.config.ts @grafana/plugins-platform-frontend
 .betterer.results @grafanabot
 .betterer.ts @grafana/grafana-frontend-platform
 
-# @grafana/ui component documentation
-*.mdx @grafana/plugins-platform-frontend
-
 # Design system
 /public/img/icons/unicons/ @grafana/design-system