docs: Fix more installation commands on Windows

[webvictim]

curl -O doesn't work in PowerShell. I tried to convert the rest of the instructions to be agnostic between cmd.exe and PowerShell, but it couldn't be done without adding tabs. Instead, I made the command more obviously PowerShell-esque.

[alexfornuto]

I was unable to run this command successfully in Windows Server 2016.

PS C:\Users\Administrator> Invoke-WebRequest -OutFile teleport-v13.0.4-windows-amd64-bin.zip -Uri https://cdn.teleport.dev/teleport-v13.0.4-windows-amd64-bin.zip
Invoke-WebRequest : The request was aborted: Could not create SSL/TLS secure channel.
At line:1 char:1
+ Invoke-WebRequest -OutFile teleport-v13.0.4-windows-amd64-bin.zip -Ur ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-WebRequest], WebException
    + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand

[webvictim]

@alexfornuto Interesting, the same command copy/pasted works fine on Windows Server 2019.

I'll investigate...

[webvictim]

@alexfornuto Can you try this?

[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
Invoke-WebRequest -OutFile teleport-v13.0.4-windows-amd64-bin.zip -Uri https://cdn.teleport.dev/teleport-v13.0.4-windows-amd64-bin.zip

Apparently Windows Server 2016 PowerShell only uses TLS 1.0 by default, but our CDN will require TLS 1.2 as a minimum.

[alexfornuto]

@webvictim that command works with 2016. If it works with 2019+ you could just use that. Otherwise we'll need to differentiate.

[webvictim]

Yes, I tested it on 2019 and it works too. I'll update the instructions.

[webvictim]

There is one more mention of curl -O for Windows here:

teleport/docs/pages/get-started.mdx

Line 183 in c1b9492

$ curl -O https://cdn.teleport.dev/teleport-v(=teleport.version=)-windows-amd64-bin.zip

It doesn't seem to actually appear anywhere in the live docs, however. I presume it's an older page that's been deprecated.

[public-teleport-github-review-bot]

@webvictim See the table below for backport results.

Branch	Result
branch/v13	Create PR