docs(custom-resources): update installLatestAwsSdk docs to specify correct version

[longtv2222]

Reason for this change

#31265

The above PR migrated the custom resource from v2 to v3, but the documentation was not updated accordingly. This update ensures the documentation reflects the correct version.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

---

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.21%. Comparing base (7be47e1) to head (8ed3435).

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #33664   +/-   ##
=======================================
  Coverage   82.21%   82.21%           
=======================================
  Files         119      119           
  Lines        6876     6876           
  Branches     1162     1162           
=======================================
  Hits         5653     5653           
  Misses       1120     1120           
  Partials      103      103           

Flag	Coverage Δ
suite.unit	82.21% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
packages/aws-cdk	∅ <ø> (∅)
packages/aws-cdk-lib/core	82.21% <ø> (ø)

[aws-cdk-automation]

AWS CodeBuild CI Report

• CodeBuild project: AutoBuildv2Project1C6BFA3F-wQm2hXv2jqQv
• Commit ID: 8ed3435
• Result: SUCCEEDED
• Build Logs (available for 30 days)

Powered by github-codebuild-logs, available on the AWS Serverless Application Repository

[samson-keung]

LGTM. Thank you

[mergify]

Thank you for contributing! Your pull request will be updated from main and then merged automatically (do not update manually, and be sure to allow changes to be pushed to your fork).

[mergify]

This pull request has been removed from the queue for the following reason: pull request branch update failed.

The pull request can't be updated

You should look at the reason for the failure and decide if the pull request needs to be fixed or if you want to requeue it.

If you want to requeue this pull request, you need to post a comment with the text: @mergifyio requeue

[mergify]

Thank you for contributing! Your pull request will be updated from main and then merged automatically (do not update manually, and be sure to allow changes to be pushed to your fork).