[Designer] `CodeBlock` element not recognized for Teams

The Adaptive Card Designer does not seem to recognize CodeBlock elements.

You can replicate by copying the example from MS Teams Adaptive Card docs into the Designer.

Error from Designer:

Code snippet:

{
  "$schema": "https://adaptivecards.io/schemas/adaptive-card.json",
  "type": "AdaptiveCard",
  "version": "1.5",
  "body": [
    {
      "type": "TextBlock",
      "text": "editor.js",
      "style": "heading"
    },
    {
      "type": "TextBlock",
      "text": "Lines 61 - 76"
    },
    {
      "type": "CodeBlock",
      "codeSnippet": "/**\n* @author John Smith <john.smith@example.com>\n*/\npackage l2f.gameserver.model;\n\npublic abstract strictfp class L2Char extends L2Object {\n  public static final Short ERROR = 0x0001;\n\n  public void moveTo(int x, int y, int z) {\n    _ai = null;\n    log(\"Shouldn't be called\");\n    if (1 > 5) { // what!?\n      return;\n    }\n  }\n}",
      "language": "java",
      "startLineNumber": 61
    }
  ],
  "actions": [
    {
      "type": "Action.OpenUrl",
      "title": "View in Azure Repos",
      "url": "https://azure.microsoft.com/en-us/products/devops/repos/"
    },
    {
      "type": "Action.OpenUrl",
      "title": "Edit in vscode.dev",
      "url": "https://vscode.dev/"
    }
  ]
}

Start in the Adaptive Card Designer and reproduce the issue with the CodeBlock example from the linked Microsoft Teams Adaptive Card documentation. Trace how the Designer handles the CodeBlock element, then verify that the example is recognized without the reported error.