Fixes for zabbix 5.4

[Dexanir]

Hello. I've made some changes to the code because (as for now) this integration can not work with zabbix 5.4 and higher due to the braking changes in API (removed apllication API, changed syntax for trigger creation). I removed application part from the code and fixed trigger syntax. Also as I can see update of the triggers don't work properly as well but I don't need that part so I didn't try to fix it.

[devopsjonas]

Thanks for this, please let me know when its ready for review :)