Port osbuild/images v0.33.0 with dot-notation to composer

Update the osbuild/images to the version which introduces "dot notation"
for distro release versions.

 - Replace all uses of distroregistry by distrofactory.
 - Delete local version of reporegistry and use the one from the
   osbuild/images.
 - Weldr: unify `createWeldrAPI()` and `createWeldrAPI2()` into a single
   `createTestWeldrAPI()` function`.
 - store/fixture: rework fixtures to allow overriding the host distro
   name and host architecture name. A cleanup function to restore the
   host distro and arch names is always part of the fixture struct.
 - Delete `distro_mock` package, since it is no longer used.
 - Bump the required version of osbuild to 98, because the OSCAP
   customization is using the 'compress_results' stage option, which is
   not available in older versions of osbuild.

Signed-off-by: Tomáš Hozza <thozza@redhat.com>

vendor/github.com/containers/storage/pkg/dmesg/dmesg_linux.go

@@ -0,0 +1,21 @@
+//go:build linux
+// +build linux
+
+package dmesg
+
+import (
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+// Dmesg returns last messages from the kernel log, up to size bytes
+func Dmesg(size int) []byte {
+	t := uintptr(3) // SYSLOG_ACTION_READ_ALL
+	b := make([]byte, size)
+	amt, _, err := unix.Syscall(unix.SYS_SYSLOG, t, uintptr(unsafe.Pointer(&b[0])), uintptr(len(b)))
+	if err != 0 {
+		return []byte{}
+	}
+	return b[:amt]
+}