Dockerfile: Windows: update Golang download domains to cut down redirects

The `golang.org` domain moved to `go.dev`, and the download-URLs we were
using resulted in 2 redirects;

    curl -sI https://golang.org/dl/go1.20.windows-amd64.zip | grep 'location'
    location: https://go.dev/dl/go1.20.windows-amd64.zip

    curl -sI https://go.dev/dl/go1.20.windows-amd64.zip | grep 'location'
    location: https://dl.google.com/go/go1.20.windows-amd64.zip

    curl -sI https://dl.google.com/go/go1.20.windows-amd64.zip
    HTTP/2 200
    # ...

This patch cuts it down to one redirects. I decided not to use the "final"
(`dl.google.com`) URL, because that URL is not documented in the Golang docs,
and visiting the domain itself (https://dl.google.com/) redirects to a marketing
page for "Google Chrome".

Trying the `/go/` path (https://dl.google.com/go/) also does not show a landing
page that lists downloads, so I'm considering those URLs to be "unstable".

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Dockerfile.windows

@@ -220,7 +220,7 @@ RUN `
   `
   Write-Host INFO: Downloading go...; `
   $dlGoVersion=$Env:GO_VERSION -replace '\.0$',''; `
-  Download-File "https://golang.org/dl/go${dlGoVersion}.windows-amd64.zip" C:\go.zip; `
+  Download-File "https://go.dev/dl/go${dlGoVersion}.windows-amd64.zip" C:\go.zip; `
   `
   Write-Host INFO: Downloading compiler 1 of 3...; `
   Download-File https://raw.githubusercontent.com/moby/docker-tdmgcc/master/gcc.zip C:\gcc.zip; `