doc: better curl command for quick start

[yihong0618]

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What's changed and what's your intention?

Doc: change curl to curl -L
I quick start using the command in README but nothing happens in my env

my env Mac m3 and zsh.
so I try to follow the doc the curl command maybe better for curl -L as risingwave doc

and I just search found this commit risingwavelabs/risingwave-docs@9648cd7#diff-dabe5e14f331ca280d6694cbb8b4f0bd1d640acf779051dc4f6c1e01504fd051R18

I think the README doc should follow the doc for the same command, And I open this doc patch

Checklist

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