update email template

[StephanieBr]

Button is now in a table since it breaks in outlook otherwise.

[jace]

I'm waiting on sample emails to proceed with the review.

[jace]

There is too much whitespace in this template.

[vidya-ram]

Fixed the width of the wrapper and content box

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

:white_check_mark: vidya-ram
:x: Stephanie Br

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