The existing test cases for `image-installer` image type were not
regenerated as part of PR #2135 which introduced 'image_type_tags'
because regenerating them using `generate-all-test-cases` failed on them
due to trying to analyze them using 'image-info'. These test cases were
most probably originally generated manually with --keep-image-info
option passed to `generate-test-cases`. And I missed that their
regeneration failed at that time.
Add the `image-installer` image type to all distros in
`distro-arch-imagetype-map.json` and (re)generate the test cases for it.
The image test case for CentOS Stream 9 is not generated, because there
are no repos defined yet for the distro. This is part of the CentOS 9
PR #2142.
Signed-off-by: Tomas Hozza <thozza@redhat.com>