chore(docs): fix layer version in CDK example

[daschaa]

Description of your changes

The version for the layer was changed from version 18 to 24.

Related issues, RFCs

Issue number: fixes #1793

Checklist

• My changes meet the tenets criteria
• I have performed a self-review of my own code
• I have commented my code where necessary, particularly in areas that should be flagged with a TODO, or hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my change is effective and works
• The PR title follows the conventional commit semantics

Breaking change checklist

Is it a breaking change?: NO

• I have documented the migration process
• I have added, implemented necessary warnings (if it can live side by side)

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[boring-cyborg]

Thanks a lot for your first contribution! Please check out our contributing guidelines and don't hesitate to ask whatever you need.
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[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[dreamorosi]

Hi @daschaa, thank you for opening this PR.

if you could please leave a comment under the linked issue I'll assign it to you before merging (GitHub doesn't allow me to assign it before one interacts with it).

[dreamorosi]

Thank you for the PR!

[daschaa]

@dreamorosi Done 😊

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!