docs: add comment in create project guide

[appleSimple]

Description

When I create new project using Vite CLI, make a directory that scaffolding new project. Then run the prompts, make new directory become overlapped. I must move folder that made by prompts outside and delete folder that I made first. This way is very conbersome I feel, I want to make new project in my existing directory. I could find the compact solution in create-vite docs. The solution is very simple but this information is hiding. Many people have this experience like me and they don't know the solution. Because it's not big problems.

I want to announce this solution. It's only one sentence!

[bolt-new-by-stackblitz[bot]]

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