ccruntime: Set containerd / nydus-snapshotter env vars globally

In theory those could very well be set only for the pre-install /
post-uninstall, but that doesn't make much sense as the user experience
on setting those would be to having to set those twice.

With the user experience in mind, let's just move them to the global env
vars and let the user set / kustomize them only once.

Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>

config/samples/ccruntime/base/ccruntime.yaml

@@ -82,27 +82,6 @@ spec:
             path: /var/lib/containerd-nydus/
             type: ""
           name: containerd-nydus
-      environmentVariables:
-        # If set to true, this will install the CoCo fork of the containerd,
-        # the one allowing images to be pulled inside the guest and has patches
-        # for handling GPU / VFIO, on the node
-        # default: true
-        - name: "INSTALL_COCO_CONTAINERD"
-          value: "false"
-        # If set to true, this will install the v1.7.0 release of containerd on the node.
-        # default: false
-        - name: "INSTALL_OFFICIAL_CONTAINERD"
-          value: "true"
-        # If set to true, this will install the CoCo fork of the containerd,
-        # the one that has patches for handling GPU / VFIO, on the node
-        # default: false
-        - name: "INSTALL_VFIO_GPU_CONTAINERD"
-          value: "false"
-        # If set to true, this will install nydus-snapshotter and nydus-image
-        # on the node
-        # default: false
-        - name: "INSTALL_NYDUS_SNAPSHOTTER"
-          value: "true"
     preInstall:
       image: quay.io/confidential-containers/reqs-payload
       volumeMounts:
@@ -137,26 +116,6 @@ spec:
             path: /var/lib/containerd-nydus/
             type: ""
           name: containerd-nydus
-      environmentVariables:
-        # If set to true, this will install the CoCo fork of the containerd,
-        # the one allowing images to be pulled inside the guest and has patches
-        # for handling GPU / VFIO, on the node
-        - name: "INSTALL_COCO_CONTAINERD"
-          value: "false"
-        # If set to true, this will install the v1.7.0 release of containerd on the node.
-        # default: false
-        - name: "INSTALL_OFFICIAL_CONTAINERD"
-          value: "true"
-        # If set to true, this will install the CoCo fork of the containerd,
-        # the one that has patches for handling GPU / VFIO, on the node
-        # default: false
-        - name: "INSTALL_VFIO_GPU_CONTAINERD"
-          value: "false"
-        # If set to true, this will install nydus-snapshotter and nydus-image
-        # on the node
-        # default: false
-        - name: "INSTALL_NYDUS_SNAPSHOTTER"
-          value: "true"
     environmentVariables:
       - name: NODE_NAME
         valueFrom:
@@ -167,3 +126,24 @@ spec:
         value: "yes"
       - name: "DEBUG"
         value: "false"
+      # If set to true, this will install the CoCo fork of the containerd,
+      # the one allowing images to be pulled inside the guest and has patches
+      # for handling GPU / VFIO, on the node
+      # default: true
+      - name: "INSTALL_COCO_CONTAINERD"
+        value: "false"
+      # If set to true, this will install the v1.7.0 release of containerd on the node.
+      # default: false
+      - name: "INSTALL_OFFICIAL_CONTAINERD"
+        value: "true"
+      # If set to true, this will install the CoCo fork of the containerd,
+      # the one that has patches for handling GPU / VFIO, on the node
+      # default: false
+      - name: "INSTALL_VFIO_GPU_CONTAINERD"
+        value: "false"
+      # If set to true, this will install nydus-snapshotter and nydus-image
+      # on the node
+      # default: false
+      - name: "INSTALL_NYDUS_SNAPSHOTTER"
+        value: "true"
+