Focusing out of the Check command field during the Host Object creation crashes site.

[w1ll-i-code]

Expected Behavior

I want to receive a error message under the field if I enter a wrong command instead of a crash where I have to redo everything.

Current Behavior

If I focus out of the Check command field during the creation of a new object the whole site crashes.

Steps to Reproduce (for bugs)

• Try creating a host template
• give it a invalid value as check command
• Notice that the site completely crashes instead of giving you just an error message./

Your Environment

• Director version (System - About): 1.11.0
• Icinga Web 2 version and modules (System - About): 2.10.5
• Icinga 2 version (icinga2 --version): r2.14.0-1
• Operating System and version: rhel 8.9
• Webserver, PHP versions: 7.4.33