/etc/hostname is empty when RHEL9 is installed without hostname setting.

Issue

• In a newer installed RHEL9 system, /etc/hostname is empty when the system is installed without hostname setting.

# cat /etc/hostname

# hostname
localhost.localdomain 
# hostnamectl
   Static hostname: (unset)
Transient hostname: localhost
         Icon name: computer-vm
           Chassis: vm
        Machine ID: 3fb65b43c78c40678a95ce7465f0041c
           Boot ID: 28cc48f6d7d04a859c2af9b7c1cfbb61
    Virtualization: 
  Operating System: Red Hat Enterprise Linux 9.3 (Plow)     
       CPE OS Name: cpe:/o:redhat:enterprise_linux:9::baseos
            Kernel: Linux 5.14.0-362.8.1.el9_3.x86_64
      Architecture: x86-64

• In past RHEL7 and RHEL8, /etc/hostname is set as "localhost.localdomain " when the system is installed without hostname setting.

# cat /etc/hostname
localhost.localdomain
# hostname
localhost.localdomain 
# hostnamectl
   Static hostname: localhost.localdomain
         Icon name: computer-vm
           Chassis: vm
        Machine ID: 1b5c61eb3d904caba9a3ce019fb2ec9d
           Boot ID: a39338d74de7489b82ea125cf55b88e2
    Virtualization: 
  Operating System: Red Hat Enterprise Linux 8.10 (Ootpa)
       CPE OS Name: cpe:/o:redhat:enterprise_linux:8::baseos
            Kernel: Linux 4.18.0-553.el8_10.x86_64
      Architecture: x86-64