The PowerShell install instructions advise the user to run Set-ExecutionPolicy manually, then do it for them anyway

## What New Or Updated Would You Like To See?

The [instructions for installing Chocolatey via PowerShell](https://docs.chocolatey.org/en-us/choco/setup#install-with-powershell.exe) currently read:

> #### Install with PowerShell.exe
> With PowerShell, there is an additional step. You must ensure [Get-ExecutionPolicy](https://go.microsoft.com/fwlink/?LinkID=135170) is not `Restricted`. We suggest using `Bypass` to bypass the policy to get things installed or `AllSigned` for quite a bit more security.
>
> * Run `Get-ExecutionPolicy`. If it returns `Restricted`, then run `Set-ExecutionPolicy AllSigned` or `Set-ExecutionPolicy Bypass -Scope Process`.
> * Now run the following command:
>
> ```ps1
> Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))
> ```

That first bullet point is rendered entirely moot by the inclusion of that same command in the second bullet's prepared command line. The first step should be removed.

## Why Is It Needed?

It's redundant, pointless, and for some users probably confusing, to tell them to explicitly run a command manually, only to include the same command in the copy-paste commandline they're provided with immediately after.

## Additional Context?

IMHO it's _entirely_ appropriate for the install instructions to provide an **explanation** of what `Set-ExecutionPolicy` does, what the different forms mean and their implications, and why it needs to be used when installing Chocolatey. The user should have a full understanding of any commands they're being asked to run, even by copy-paste. (Especially by copy-paste!)

So, the notes about using `Get-ExecutionPolicy` to check the status, or potentially using `AllSigned` as the policy instead of `Bypass`, are all worthwhile content to be included in the instructions. But since that information would be an optional, "further reading"-type discussion (digression, really, for users who are already familiar with the execution policy features), rather than a required step in the install process, it should be contextualized appropriately.

Because once the decision has been made to include `Set-ExecutionPolicy Bypass -Scope Process` as part of the copy-paste install command, explicitly _instructing_ the user to first manually run the exact same command for themselves (a totally unnecessary step) is just wasting their time.