message: Update the debugger to 1-12-4
  This updates the debugger packages to one that has the fix for issue 1655 (missing OSX .ni files).
diff: },
  {
  "description": ".NET Core Debugger (Windows / x64)",
  - "url": "https://download.visualstudio.microsoft.com/download/pr/10950340/4d5e39c15f4229a200bc1956621758fe/coreclr-debug-win7-x64.zip",
  - "fallbackUrl": "https://vsdebugger.blob.core.windows.net/coreclr-debug-1-12-3/coreclr-debug-win7-x64.zip",
  + "url": "https://download.visualstudio.microsoft.com/download/pr/10966208/a75c00c88407dbc32ceaaa4e0c84f88d/coreclr-debug-win7-x64.zip",
  + "fallbackUrl": "https://vsdebugger.blob.core.windows.net/coreclr-debug-1-12-4/coreclr-debug-win7-x64.zip",
  "installPath": ".debugger",
  "platforms": [
  "win32"
  },
  {
  "description": ".NET Core Debugger (macOS / x64)",
  - "url": "https://download.visualstudio.microsoft.com/download/pr/10950340/4d5e39c15f4229a200bc1956621758fe/coreclr-debug-osx.10.11-x64.zip",
  - "fallbackUrl": "https://vsdebugger.blob.core.windows.net/coreclr-debug-1-12-3/coreclr-debug-osx.10.11-x64.zip",
  + "url": "https://download.visualstudio.microsoft.com/download/pr/10966208/a75c00c88407dbc32ceaaa4e0c84f88d/coreclr-debug-osx.10.11-x64.zip",
  + "fallbackUrl": "https://vsdebugger.blob.core.windows.net/coreclr-debug-1-12-4/coreclr-debug-osx.10.11-x64.zip",
  "installPath": ".debugger",
  "platforms": [
  "darwin"
  },
  {
  "description": ".NET Core Debugger (linux / x64)",
  - "url": "https://download.visualstudio.microsoft.com/download/pr/10950340/4d5e39c15f4229a200bc1956621758fe/coreclr-debug-linux-x64.zip",
  - "fallbackUrl": "https://vsdebugger.blob.core.windows.net/coreclr-debug-1-12-3/coreclr-debug-linux-x64.zip",
  + "url": "https://download.visualstudio.microsoft.com/download/pr/10966208/a75c00c88407dbc32ceaaa4e0c84f88d/coreclr-debug-linux-x64.zip",
  + "fallbackUrl": "https://vsdebugger.blob.core.windows.net/coreclr-debug-1-12-4/coreclr-debug-linux-x64.zip",
  "installPath": ".debugger",
  "platforms": [
  "linux"
  