fix(WeatherStatus): Check if result is an array

[solracsf]

Summary

Fix:

{
  "reqId": "JbpwgXOXkV33ULwTfBku",
  "level": 3,
  "time": "2025-04-29T16:39:11+02:00",
  "remoteAddr": "6.17.12.8",
  "user": "ezdf",
  "app": "PHP",
  "method": "PUT",
  "url": "/ocs/v2.php/apps/weather_status/api/v1/location",
  "message": "Undefined array key \"error\" at /var/www/nextcloud/apps/weather_status/lib/Service/WeatherStatusService.php#260",
  "userAgent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
  "version": "30.0.9.2",
  "data": {
    "app": "PHP"
  },
  "id": "6811b29447190"
}

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[solracsf]

/backport to stable30

[solracsf]

/backport to stable31