fix(sveltekit): Guard process variable (#15605)

`process` was guarded in
#15516 already, but
it still did not fix the problem as the variable `process` is not even
available so the code still broke. This is another attempt to fix
"process is undefined" reported in
#15506

Author: s1gr1d

packages/sveltekit/src/server-common/utils.ts

@@ -19,7 +19,7 @@ export function getTracePropagationData(event: RequestEvent): { sentryTrace: str
 
 /** Flush the event queue to ensure that events get sent to Sentry before the response is finished and the lambda ends */
 export async function flushIfServerless(): Promise<void> {
-  if (!process) {
+  if (typeof process === 'undefined') {
     return;
   }