Revert "[CI][Github] Bump Windows Container to Server 2022"

Seems like this is the wrong approach.
This reverts commit bc91ef4.

Author: bcardosolopes

.github/workflows/build-ci-container-windows.yml

@@ -18,7 +18,7 @@ on:
 jobs:
   build-ci-container-windows:
     if: github.repository_owner == 'llvm'
-    runs-on: windows-2022
+    runs-on: windows-2019
     outputs:
       container-name: ${{ steps.vars.outputs.container-name }}
       container-name-tag: ${{ steps.vars.outputs.container-name-tag }}
@@ -32,7 +32,7 @@ jobs:
         id: vars
         run: |
           $tag = [int64](Get-Date -UFormat %s)
-          $container_name="ghcr.io/$env:GITHUB_REPOSITORY_OWNER/ci-windows-2022"
+          $container_name="ghcr.io/$env:GITHUB_REPOSITORY_OWNER/ci-windows-2019"
           echo "container-name=${container_name}" >> $env:GITHUB_OUTPUT
           echo "container-name-tag=${container_name}:${tag}" >> $env:GITHUB_OUTPUT
           echo "container-filename=ci-windows-${tag}.tar" >> $env:GITHUB_OUTPUT
@@ -56,7 +56,7 @@ jobs:
       - build-ci-container-windows
     permissions:
       packages: write
-    runs-on: windows-2022
+    runs-on: windows-2019
     env:
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:

.github/workflows/containers/github-action-ci-windows/Dockerfile

@@ -1,6 +1,6 @@
 # Agent image for LLVM org cluster.
 # .net 4.8 is required by chocolately package manager.
-FROM mcr.microsoft.com/dotnet/framework/sdk:4.8-windowsservercore-ltsc2022
+FROM mcr.microsoft.com/dotnet/framework/sdk:4.8-windowsservercore-ltsc2019
 
 # Restore the default Windows shell for correct batch processing.
 SHELL ["cmd", "/S", "/C"]