docs(js): Clarify behavior of timeoutWarningLimit in AWS (#14286)

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resolves getsentry/sentry-javascript#9810

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Author: msonnb

docs/platforms/javascript/guides/aws-lambda/configuration/lambda-wrapper.mdx

@@ -20,19 +20,19 @@ exports.handler = Sentry.wrapHandler(yourHandler, {
 
 ## Timeout Warning
 
-Sentry reports timeout warnings when the Lambda function is within 500ms of its execution time. You can turn off timeout warnings by setting `captureTimeoutWarning` to `false` in the handler options.
+Sentry reports timeout warnings when the Lambda function is within 500ms of the configured Lambda timeout. You can turn off timeout warnings by setting `captureTimeoutWarning` to `false` in the handler options.
 
 ```javascript {filename:index.js} {2}
 exports.handler = Sentry.wrapHandler(yourHandler, {
   captureTimeoutWarning: false,
 });
 ```
 
-To change the timeout warning limit, assign a numeric value (in ms) to `timeoutWarningLimit`:
+To change the timeout warning limit, assign a numeric value (in ms) to `timeoutWarningLimit`. This value specifies the time left before the warning is triggered.
 
 ```javascript {filename:index.js} {2}
 exports.handler = Sentry.wrapHandler(yourHandler, {
-  timeoutWarningLimit: 700,
+  timeoutWarningLimit: 700, // Warn when within 700ms of timeout
 });
 ```