cleanup: use vaultDefaultCAVerify to set default value
cleanup: use vaultDefaultCAVerify to set default value

Golang-ci complains about the following:

    internal/util/vault_tokens.go:99:20: string `true` has 4 occurrences, but such constant `vaultDefaultDestroyKeys` already exists (goconst)
    	v.VaultCAVerify = "true"
    	                  ^

This occurence of "true" can be replaced by vaultDefaultCAVerify so
address the warning.

Signed-off-by: Niels de Vos <7bda0c0ee7f47171cc808e9e60292cbc5d8140dd@redhat.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi