move namespace param from Worker to Client - project-setup.mdx

[bkcsfi]

Worker() does not accept namespace, it must be passed to Client.connect() instead.

Since namespaces are introduced later in this document, a better fix might be to simply eliminate the namespace parameter from this example, rather than moving it to Client.connect().

[CLAassistant]

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[flossypurse]

@bkcsfi - Thank you! I picked up your change here: https://github.com/temporalio/documentation/pull/2751 There was an additional spot in the source code that needed the namespace as well and we have since re-orged the docs which would have made merging or rebasing main a bit of pain - so that's why I picked it up for you.