Update install with install_zabbix_repo function

scripts/install

@@ -99,9 +99,7 @@ ynh_print_info "Remove Zabbix if already installed"
 apt purge zabbix* -y
 
 ynh_print_info "Install Zabbix repository"
-ynh_add_extra_apt_repos__3_path=$(find /var/cache/yunohost/ -name "ynh_add_extra_apt_repos__3")
-source "$ynh_add_extra_apt_repos__3_path"
-ynh_install_extra_repo --repo=http://repo.zabbix.com/zabbix/4.2/debian --key=https://repo.zabbix.com/zabbix-official-repo.key  --priority=999
+install_zabbix_repo
 
 ynh_print_info "Update and install dependencies"
 #ynh_package_update no need cause ynh_install_app_dependencies after