test: add specs for version command with spec/dummy app

spec/command/version_spec.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+
+describe Command::Version, parallel: true, slow: false do
+  it "displays version" do
+    result = run_command("version")
+
+    expect(result[:status]).to eq(0)
+    expect(result[:stdout]).to include(Cpl::VERSION)
+  end
+end