feat: require valid admin email for platform start

[zerbitx]

What issue type does this pull request address? (keep at least one, remove the others) /kind enhancement

What does this pull request do? Which issues does it resolve? (use resolves #<issue_number> if possible) resolves #ENG-3850

What else do we need to know?

💡 The go:geneate portion can be removed if its seen as "overkill", I threw it in to make updating the list easier in the future.

Requirements from the issue:

If in interactive shell, then prompt for email address. With the email address:

Check if Valid Email - use a parser

Don't allow any disposable emails: Use this list to verify if it's a disposable one. This is in the existing email-verifier library. https://raw.githubusercontent.com/disposable/disposable-email-domains/master/domains.json 

Check if mx_record is found

Connect to see if it's valid with a 10 second timeout. If it doesn't come back in 10 seconds, it's considered invalid.

If the validation step doesn't succeed, then keep asking the question.

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[deniseschannon]

@FabianKramm It looks like most of this code changes are from packaging the disposable domains. That file alone is 169,412 lines of code.

[deniseschannon]

@zerbitx - Let's do this. Let's replace the list with this much smaller one: https://github.com/disposable-email-domains/disposable-email-domains/blob/main/disposable_email_blocklist.conf

That will significantly decrease the size of the PR.

[zerbitx]

@deniseschannon @FabianKramm I changed the list to be a zip file to make it smaller as an embed, using the condensed list suggested.