Feature: Added process to create RHEL 9 image using ansible-image-builder

[enothen]

Description

• Added process to create qcow2 image using Red Hat Insights Image Builder through the ansible-image-builder role
• Added new process to documentation and release notes
• Implements [RFE] RHEL9 deployment could be automated using insights image builder [RFE] RHEL9 deployment could be automated using insights image builder #328

Checklist/ToDo's

• Added documentation
• Added release note entry
• Tested

[enothen]

@rbo a couple of things here:

1. I have tested the tarball generation process, but I have not tested that tar with Hetzner, simply because I can't destroy my single server right now. Do you have availability to test that and provide feedback?
2. I leave it up to you to rename the playbooks, since there's now two files called 00-*
3. In regards to the customization that is done on the manual process and how it works on the image-builder process:

• subscription-manager registration: Not required to register, nor to unregister afterwards
• installing packages: Done on the image definition itself (if anything else is needed, add it to the image definition)
• dnf upgrade: Not required. Image builder uses latest content on the repositories.
• Adding rd.auto: Done on the image definition as an image-builder customization of type kernel
• Disabling system.devices: Removing the file is not required, this file is not present on the image. Changing the value of use_devicesfile in lvm.conf is done as part of the image definition (see offline_customizations)
• Symlink for dracut: There's no customization method on the image builder API for adding a symlink, so this is done using as an offline customization (same as above, see the image definition)
• Removing iwl* rpms: Not required as they are not installed on the image
• Cleanup (OS sealing): Not required, this image was never actually booted

[enothen]

Some validation:

$ tar -tJf ./rhel9-hetzner-ocp4.tar.xz | grep bin/dracut
./usr/bin/dracut
./usr/sbin/dracut
$ tar -xJf ./rhel9-hetzner-ocp4.tar.xz ./etc/lvm/lvm.conf ./etc/default/grub 
$ grep use_device etc/lvm/lvm.conf 
	# Configuration option devices/use_devicesfile.
	use_devicesfile = 0
$ grep rd.auto etc/default/grub 
GRUB_CMDLINE_LINUX="console=tty0 console=ttyS0,115200n8 no_timer_check net.ifnames=0 rd.auto"