fix: added validation to the Community Newsletter form

[aakankshabhende]

Description
Added validation to the Community Newsletter form, the first name and last name should accept alphabetical input only.

This PR fixes #1974

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[vishalvivekm]

@aakankshabhende
Let's discuss this on websites call on Monday at 6:30 PM IST (7:00 AM CT). Add it as an agenda item to the meeting minutes, if you would :)

[leecalcote]

@aakankshabhende thanks for this. Are we ready for review here or still in-draft?

[aakankshabhende]

Yes, its still in draft, I'll send a fix for styling and minimum length requirement and make it ready to review.

[leecalcote]

@Venkata-Sai-Vishwanath-robo would you like to offer review on this PR?

[Venkata-Sai-Vishwanath-robo]

@Venkata-Sai-Vishwanath-robo would you like to offer review on this PR?

Sure, @leecalcote! I would love to take it on. I’ll do my best to provide helpful feedback and appreciate your understanding as I learn through this process.