fix: Cleanup timeout timer for waitForInitialization (#478)

Use the new cancelable timer to ensure that the handle gets cleaned up.

packages/shared/sdk-server/src/LDClientImpl.ts

@@ -1,5 +1,6 @@
 /* eslint-disable class-methods-use-this */
 import {
+  cancelableTimedPromise,
   ClientContext,
   Context,
   internal,
@@ -11,7 +12,6 @@ import {
   LDTimeoutError,
   Platform,
   subsystem,
-  timedPromise,
   TypeValidators,
 } from '@launchdarkly/js-sdk-common';
 
@@ -911,8 +911,11 @@ export default class LDClientImpl implements LDClient {
     logger?: LDLogger,
   ): Promise<LDClient> {
     if (timeout) {
-      const timeoutPromise = timedPromise(timeout, 'waitForInitialization');
-      return Promise.race([basePromise, timeoutPromise.then(() => this)]).catch((reason) => {
+      const cancelableTimeout = cancelableTimedPromise(timeout, 'waitForInitialization');
+      return Promise.race([
+        basePromise.then(() => cancelableTimeout.cancel()).then(() => this),
+        cancelableTimeout.promise.then(() => this),
+      ]).catch((reason) => {
         if (reason instanceof LDTimeoutError) {
           logger?.error(reason.message);
         }