Added FAQ on sending email to sending not registerd user in harness

[abhi-harness-cxe]

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Description

• Please describe your changes: Added FAQ on sending email to sending not registerd user in harness
• Jira/GitHub Issue numbers (if any): ______________________________
• Preview links/images (Internal contributors only): __________________

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[bot-gitexp-user]

Please check the Execution Link of the Pipeline for the Website Draft URL. This is located in the Preview Step behind the Harness VPN and also is available in #hdh_alerts. E.g Website Draft URL: https://unique-id--harness-developer.netlify.app. Current Draft URL is: https://66e94b3a1a6ba6d30e1c18df--harness-developer.netlify.app

[bot-gitexp-user]

Please check the Execution Link of the Pipeline for the Website Draft URL. This is located in the Preview Step behind the Harness VPN and also is available in #hdh_alerts. E.g Website Draft URL: https://unique-id--harness-developer.netlify.app. Current Draft URL is: https://66f502012292d0799cb1e14a--harness-developer.netlify.app