Apply suggestions from code review

Co-authored-by: Alex Krawiec <[email protected]>

Author: krystofwoldrich

docs/platforms/react-native/tracing/instrumentation/performance-metrics.mdx

@@ -6,12 +6,10 @@ sidebar_order: 20
 
 Sentry's SDKs support sending performance metrics data to Sentry. These are numeric values attached to transactions that are aggregated and displayed in Sentry.
 
-If configured, the React Native SDK automatically collects the following performance metrics:
+The React Native SDK automatically collects the following performance metrics:
 
 - <PlatformLink to="/tracing/instrumentation/automatic-instrumentation/#app-start-instrumentation"> Cold and warm app start time </PlatformLink>
-  .
 - <PlatformLink to="/tracing/instrumentation/automatic-instrumentation/#slow-and-frozen-frames"> Slow and frozen frame rendering </PlatformLink>
-  .
 
 ## Custom Measurements