yq: failed traversing anchors in version.yaml

The latest yq might not "resolve" the anchor, if it refers to
an scalar (string, integer etc). But it's fine with the collections
(sequences, mappings).

Fixes: 2430

Signed-off-by: Penny Zheng <penny.zheng@arm.com>

versions.yaml

@@ -125,30 +125,24 @@ assets:
       s390x:
         name: "ubuntu"
         version: "latest"
-      x86_64:
-        name: &default-image-name "clearlinux"
+      x86_64: &default-image
+        name: "clearlinux"
         version: "latest"
     meta:
-      image-type: *default-image-name
+      image-type: *default-image
 
   initrd:
     description: |
       Root filesystem initrd used to boot the guest virtual
       machine.
     url: "https://github.com/kata-containers/osbuilder"
     architecture:
-      aarch64:
-        name: &default-initrd-name "alpine"
-        version: &default-initrd-version "3.7"
-      ppc64le:
-        name: *default-initrd-name
-        version: *default-initrd-version
-      s390x:
-        name: *default-initrd-name
-        version: *default-initrd-version
-      x86_64:
-        name: *default-initrd-name
-        version: *default-initrd-version
+      aarch64: &default-initrd
+        name: "alpine"
+        version: "3.7"
+      ppc64le: *default-initrd
+      s390x: *default-initrd
+      x86_64: *default-initrd
 
   kernel:
     description: "Linux kernel optimised for virtual machines"