added twitter tracking pixel

[brinnpaul]

[juanshishido]

Thanks for this, @brinnpaul! The team will take a look this coming week.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}