Fix undefined when no tags

[kesselb]

To reproduce:

Run tag:list without having any tags ;)

{
  "reqId": "lP0erYeSlc6i8SLp6fcp",
  "level": 3,
  "time": "2022-06-10T15:54:16+00:00",
  "remoteAddr": "",
  "user": "--",
  "app": "PHP",
  "method": "",
  "url": "--",
  "message": "Undefined variable: result at httpdocs/core/Command/SystemTag/ListCommand.php#82",
  "userAgent": "--",
  "version": "22.2.8.1",
  "exception": {
    "Exception": "Error",
    "Message": "Undefined variable: result at httpdocs/core/Command/SystemTag/ListCommand.php#82",
    "Code": 0,
    "Trace": [
      {
        "file": "httpdocs/core/Command/SystemTag/ListCommand.php",
        "line": 82,
        "function": "onError",
        "class": "OC\\Log\\ErrorHandler",
        "type": "::"
      },
      {
        "file": "httpdocs/core/Command/SystemTag/ListCommand.php",
        "line": 67,
        "function": "formatTags",
        "class": "OC\\Core\\Command\\SystemTag\\ListCommand",
        "type": "->"
      },
      {
        "file": "httpdocs/3rdparty/symfony/console/Command/Command.php",
        "line": 255,
        "function": "execute",
        "class": "OC\\Core\\Command\\SystemTag\\ListCommand",
        "type": "->"
      },
      {
        "file": "httpdocs/core/Command/Base.php",
        "line": 168,
        "function": "run",
        "class": "Symfony\\Component\\Console\\Command\\Command",
        "type": "->"
      },
      {
        "file": "httpdocs/3rdparty/symfony/console/Application.php",
        "line": 1009,
        "function": "run",
        "class": "OC\\Core\\Command\\Base",
        "type": "->"
      },
      {
        "file": "httpdocs/3rdparty/symfony/console/Application.php",
        "line": 273,
        "function": "doRunCommand",
        "class": "Symfony\\Component\\Console\\Application",
        "type": "->"
      },
      {
        "file": "httpdocs/3rdparty/symfony/console/Application.php",
        "line": 149,
        "function": "doRun",
        "class": "Symfony\\Component\\Console\\Application",
        "type": "->"
      },
      {
        "file": "httpdocs/lib/private/Console/Application.php",
        "line": 209,
        "function": "run",
        "class": "Symfony\\Component\\Console\\Application",
        "type": "->"
      },
      {
        "file": "httpdocs/console.php",
        "line": 99,
        "function": "run",
        "class": "OC\\Console\\Application",
        "type": "->"
      },
      {
        "file": "httpdocs/occ",
        "line": 11,
        "args": [
          "httpdocs/console.php"
        ],
        "function": "require_once"
      }
    ],
    "File": "httpdocs/lib/private/Log/ErrorHandler.php",
    "Line": 92,
    "CustomMessage": "--"
  },
  "id": "62a6fa1003960"
}

[come-nc]

👍

[kesselb]

/backport to stable24

[backportbot-nextcloud]

The backport to stable24 failed. Please do this backport manually.