feat: add sdk docs as part of build

[itsacoyote]

What :computer:

• Add sdk as part of the docs build

Why :hand:

• Currently sdk repo cannot deploy to a separate host as we don't have the means to set up a reverse proxy to handle /sdk.
• This includes the sdk build into docs so that it all goes out in one deploy.

[github-actions[bot]]

Visit the preview URL for this PR (updated for commit 66d45c7):

https://zksync-docs-staging-5eb09--pr80-add-sdk-7zdaoc8o.web.app

_{(expires Tue, 28 May 2024 00:24:06 GMT)}

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