Revert "Hardcode version of yq on 3.3.2"

This reverts commit bdb9b120a93f7b6513f396a9bbac424097b6726e.

Reason for revert: instance_boot is too huge

Change-Id: I5f009e13e49fbee5c9ef2b8ab4691234698fd696
diff --git a/de/heat-templates/scripts/instance_boot.sh b/de/heat-templates/scripts/instance_boot.sh
index cccbc3a..5950eff 100644
--- a/de/heat-templates/scripts/instance_boot.sh
+++ b/de/heat-templates/scripts/instance_boot.sh
@@ -217,11 +217,9 @@
         fi
     fi
     function install_retry {
+        add-apt-repository ppa:rmescandon/yq -y
         apt update
-        export DEBIAN_FRONTEND=noninteractive; apt install -y $pkg_list
-        # Since version 4 yq uses another syntax
-        curl --retry 6 --retry-delay 5 -L https://github.com/mikefarah/yq/releases/download/3.3.2/yq_linux_amd64 -o /usr/bin/yq
-        chmod +x /usr/bin/yq
+        export DEBIAN_FRONTEND=noninteractive; apt install -y $pkg_list yq
     }
     retry 10 "Failed to install required packages" install_retry
 }