Fix incorrect type being passed to NativePerformance.mark

Summary:
Changelog: [internal]

In D64466057 / facebook@32f7b3b we accidentally modified the API of `NativePerformance.mark` (which we wanted to preserve and move the changes to `NativePerformance.markWithResult` after some iteration) to make `startTime` optional. This change isn't OTA safe and no automated systems caught this problem.

This fixes the issue by reverting the type back to being required and always passing it from the JS API.

Differential Revision: D64557467

packages/react-native/src/private/webapis/performance/Performance.js

@@ -116,7 +116,8 @@ export default class Performance {
         markOptions?.startTime,
       );
     } else if (NativePerformance?.mark) {
-      NativePerformance.mark(markName, markOptions?.startTime);
+      computedStartTime = markOptions?.startTime ?? performance.now();
+      NativePerformance?.mark?.(markName, computedStartTime);
     } else {
       warnNoNativePerformance();
     }

packages/react-native/src/private/webapis/performance/specs/NativePerformance.js

@@ -46,7 +46,7 @@ export type PerformanceObserverInit = {
 export interface Spec extends TurboModule {
   +now?: () => number;
   // TODO: remove when `markWithResult` is fully rolled out.
-  +mark?: (name: string, startTime?: number) => void;
+  +mark?: (name: string, startTime: number) => void;
   // TODO: remove when `measureWithResult` is fully rolled out.
   +measure?: (
     name: string,