Add step-cli for recovery (#1214)

getting_started/setup_vm/roles/ccf_build/tasks/install.yml

@@ -116,3 +116,8 @@
     mode: +x
     state: link
   become: true
+
+- name: Install step-cli
+  apt:
+    deb: "{{ step_cli }}"
+  become: true

getting_started/setup_vm/roles/ccf_build/vars/common.yml

@@ -26,3 +26,5 @@ fb_ver: "1.12.0"
 flatbuffers_src: "v{{ fb_ver }}.tar.gz"
 flatbuffers_url: "https://github.com/google/flatbuffers/archive/v{{ fb_ver }}.tar.gz"
 fb_prefix: "/opt/flatbuffers"
+step_cli_ver: "0.14.4"
+step_cli: "https://github.com/smallstep/cli/releases/download/v{{ step_cli_ver }}/step-cli_{{ step_cli_ver }}_amd64.deb"