Using ${var} in strings is deprecated

[politas]

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Explain the Problem

Log entry PHP Error - Using ${var} in strings is deprecated.

Steps to Reproduce

Explain what you did to encounter the issue

1. Opened Administration settings, saw message saying "Error encountered whilst checking server setup", opened logging and found one entry in log.

System Information

• News app version: Version 24.0.0,
• Nextcloud version: Nextcloud Hub 8 (29.0.0)
• Cron type: system cron
• PHP version: PHP 8.2.18
• Database and version: mariadb from 11.3.2-MariaDB
• Browser and version: Brave Version 1.65.123 Chromium: 124.0.6367.91 (Official Build) (64-bit)
• OS and version: "Official" Docker https://hub.docker.com/_/nextcloud/

Contents of nextcloud/data/nextcloud.log

```json {"reqId":"zjCCg4ZEl4swNTKM2eoD","level":3,"time":"2024-05-03T06:29:58+00:00","remoteAddr":"220.233.90.45","user":"admin","app":"PHP","method":"GET","url":"/settings/apps/updates","message":"Using ${var} in strings is deprecated, use {$var} instead at /var/www/html/custom_apps/news/lib/Controller/ExportController.php#64","userAgent":"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36","version":"29.0.0.19","data":{"app":"PHP"},"id":"663486576a708"} ```

[politas]

Ah, sorry, duplicate of #2601. I didn't check for closed issues.