chore: fix JavaScript lint errors (issue #9825)

[SuYaSh-PaThAk04]

Resolves - #9825

Description

What is the purpose of this pull request?

This pull request:

• Fixes a JavaScript lint error caused by an unnecessary nested function in the
  remark-stdlib-urls-www transformer.
• Moves visitor to outer scope via a factory function
• No functional changes

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• Fix JavaScript lint errors #9825

Questions

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No.

Other

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No.

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• Read, understood, and followed the contributing guidelines.

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• No

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@stdlib-js/reviewers

[Planeshifter]

Resolved via #9829 instead. Moving one level up only instead of module scope allows us to avoid having to declare a wrapper function. Thanks for opening PR!