chore: move email-preview to devDeps

[felixmosh]

Checklist

• I have ensured my pull request is not behind the main or master branch of the original repository.
• I have rebased all commits where necessary so that reviewing this pull request can be done without having to merge it first.
• I have written a commit message that passes commitlint linting.
• I have ensured that my code changes pass linting tests.
• I have ensured that my code changes pass unit tests.
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closes #453

[titanism]

You do not put require calls inside conditionals outside of root scope. It is bad practice.

[felixmosh]

How do you suggest to solve this issue? Preview-email appears in production env, even though it is not relevant there.

[felixmosh]

@titanism any update? since this is the only usage, maybe, it is better to pass the lib it self instead of the config of it.

WDYT?
It not only that preview-email is on prod env, it brings many other deps, like esprima and many more.

[titanism]

@felixmosh v12.0.0 of email-templates has been release to GitHub and npm with optional dependency of preview-email. In production environments it will console.error if you attempt to have previewEmail option with a truthy value, and in production environments it will throw.

Thank you for your feedback and patience @felixmosh

Consider supporting our efforts at https://forwardemail.net 🙏

https://github.com/forwardemail/email-templates/releases/tag/v12.0.0

[felixmosh]

Thank you! 🙏🏼