net-mgmt/icingaweb2: Fix at runtime with php 8

PR: 256656
Approved by: lme (maintainer)
Obtained from: https://github.com/Icinga/icingaweb2/commit/4bc5350ebaaeb7a60bbe20829a1d72def343a921

		https://github.com/Icinga/icingaweb2/commit/dc7a8c8d8b6eefe03a5dd66425132de3f1afdc59