Description of problem:
When creating or updating hostgoup in cli or api despite not linked architecture and operating system, host group is successfully created.

Version-Release number of selected component (if applicable):


How reproducible:
allways

Steps to Reproduce:
1. Create two architectures.
# hammer architecture create --name arch1
# hammer architecture create --name arch2
2. Create os based on architecture 1
# hammer os create --name test_os --architectures arch1 --major 1
3. Create host group with architecture 2 and os
# hammer hostgroup create --name test --architecture arch2 --operatingsystem 'test_os 1'

Actual results:
Hostgroup is crated.

# hammer hostgroup info --name test
Id:                    254
Name:                  test
Title:                 test
Network:               

Operating system:      
    Architecture:     arch2
    Operating System: test_os 1
...

# hammer os info --title 'test_os 1'
Id:                 46
Title:              test_os 1
Release name:       
Family:             
Name:               test_os
Major version:      1
...


Expected results:
Error message, architecture in os is different that architecture in hostgroup

Additional info: