Better instruction for powershell

[sharpchen]

It's not important but, it feels convoluted and redundant using scriptblock here

zoxide/README.md

Lines 270 to 272 in fcce980

	> ```powershell
	> Invoke-Expression (& { (zoxide init powershell | Out-String) })
	> ```

why not just use this, it's much more clear

zoxide init powershell | Out-String | Invoke-Expression