Auto merge of #22123 - Darkspirit:https_taskcluster_windows, r=jdm

Ensuring https for Windows Taskcluster

This should be a safe change as there're already some https downloads on Windows Taskcluster. Examples:
* with `$client.DownloadFile()`: 78327fcba5/etc/taskcluster/windows/bootstrap.ps1 (L43)
* with `Expand-ZIPFile`: e217672c1a/etc/taskcluster/windows/bootstrap.ps1 (L40)

Modern TLS is supported:
https://www.hardenize.com/report/download.tuxfamily.org#www_tls
https://www.hardenize.com/report/nssm.cc#www_tls

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etc/taskcluster/windows/bootstrap.ps1

@@ -10,13 +10,6 @@
     [EnvironmentVariableTarget]::Machine)
 
 
-# Optional
-$client.DownloadFile(
-    "http://download.tuxfamily.org/dvorak/windows/bepo.exe",
-    "C:\bepo.exe"
-)
-
-
 # use TLS 1.2 (see bug 1443595)
 [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
 
@@ -35,6 +28,12 @@ function Expand-ZIPFile($file, $destination, $url)
     }
 }
 
+# Optional
+$client.DownloadFile(
+    "https://download.tuxfamily.org/dvorak/windows/bepo.exe",
+    "C:\bepo.exe"
+)
+
 md C:\git
 Expand-ZIPFile -File "C:\git.zip" -Destination "C:\git" -Url `
     "https://github.com/git-for-windows/git/releases/download/v2.19.0.windows.1/MinGit-2.19.0-64-bit.zip"

etc/taskcluster/windows/first-boot.ps1

@@ -40,7 +40,7 @@ $client.DownloadFile("https://github.com/taskcluster/generic-worker/releases/dow
 $client.DownloadFile("https://github.com/taskcluster/livelog/releases/download" +
     "/v1.1.0/livelog-windows-amd64.exe", "C:\generic-worker\livelog.exe")
 Expand-ZIPFile -File "C:\nssm-2.24.zip" -Destination "C:\" `
-    -Url "http://www.nssm.cc/release/nssm-2.24.zip"
+    -Url "https://www.nssm.cc/release/nssm-2.24.zip"
 Start-Process C:\generic-worker\generic-worker.exe -ArgumentList `
     "new-openpgp-keypair --file C:\generic-worker\generic-worker-gpg-signing-key.key" `
     -Wait -NoNewWindow -PassThru `