chore(layers): bump hardcoded cdk version in publish_layer.yaml

[dreamorosi]

Description of your changes

As described in #1231, the publish_layer.yaml workflow contains an hardcoded version for the CDK CLI. Given that the CDK version in the project was recently updated, the version in the workflow and the one on the project were now out of sync.

As a short term solution to be able to publish the layers, this PR bumps the version and leaves it hardcoded.

I have written down the task to remove the hardcoded version in favor of using the one installed in the project, and managed in the package.json of the layer-publisher folder, in #1226.

How to verify this change

Related issues, RFCs

Issue number: #1231

PR status

Is this ready for review?: YES
Is it a breaking change?: NO

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
• I have made corresponding changes to the examples
• My changes generate no new warnings
• The code coverage hasn't decreased
• I have added tests that prove my change is effective and works
• New and existing unit tests pass locally and in Github Actions
• Any dependent changes have been merged and published
• The PR title follows the conventional commit semantics

Breaking change checklist

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

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