WebUI: incorrect validation of domain name for AD service

[Timur Nurlygayanov]

*Steps To Reproduce:*
1. Log into WebUI
2. Navigate to Project > Environments
3. Create environment 'test'
4. Navigate to the list of services for environment 'test'
5. Click on 'Create Service' button
6. Select Type = 'Active Directory' and click Next
7. Try to input domain name 'demo.murano.mirantis.com'

*Expected Result:*
User can input 'demo.murano.mirantis.com' to the domain name field. Also need to check that user can not create domain name with 15+ characters before the first '.' (like {w+15}.{w+49})

*Observed Result:*
User cano not input 'demo.murano.mirantis.com' for AD service name.