doc: update tutorial with video (#152)

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# Description

Adds video to the quickstart tutorial

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## Additional context

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Co-authored-by: Sabrina <[email protected]>

content/00.build/05.quick-start/3.deploy-your-first-contract.md

@@ -6,6 +6,9 @@ description: Deploy a smart contract to ZKsync from your browser using Remix or
 This tutorial shows you how to deploy and interact with a smart contract on ZKsync Era in less than 5 minutes.
 It will help you get familiar with the ZKsync smart contract development and deployment process using different tools.
 
+<!-- markdownlint-disable-next-line -->
+<iframe width="560" height="315" src="https://www.youtube.com/embed/gumsrrXtIsA?si=NAjA4fJJvqSpCBXZ" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe>
+
 In this section you will learn how to:
 
 :check-icon Build a smart contract to exchange messages with Zeek.