chore(tracer): remove redundant export in docs & examples

[dreamorosi]

Description of your changes

As evidenced in this review comment, the examples, the docstrings, and the documentation had a redundant export when it comes to showing how use a Lambda handler as a class:

Before

class Lambda implements LambdaInterface {}

export const handlerClass = new Lambda();
export const handler = handlerClass.handler.bind(handlerClass);

After

class Lambda implements LambdaInterface {}

const handlerClass = new Lambda(); // <- Removes export
export const handler = handlerClass.handler.bind(handlerClass);

This PR addresses the change given that the related PR has already been merged. Similar changes have been applied to the other two PRs still open.

How to verify this change

See updated docs/examples/docstrings.

Related issues, RFCs

Issue number:#1056

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 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
• New and existing unit tests pass locally and in Github Actions
• The PR title follows the conventional commit semantics

Breaking change checklist

N/A

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