test(inspec): verify map.jinja dump

We store validated `map.jinja` dump under the profile `files`
directory to access them with `inspec.profile.file('filename')` to
validate the content of the generated mapdata file.

The YAML files contain a value specific to each minion, its hostname,
so we use string format to expand `%{hostname}`.

The `default` inspec profile need to depends on `share` to access the
`system` and `salt_minion` libraries.

test/integration/default/controls/_mapdata_spec.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+# Replace per minion strings
+replacement = {
+  hostname: system.hostname
+}
+
+mapdata_file = "mapdata/#{system.platform[:finger].split('.').first}.yaml"
+mapdata_dump = inspec.profile.file(mapdata_file) % replacement
+
+control '`map.jinja` YAML dump' do
+  title 'should contain the lines'
+
+  describe file('/tmp/salt_mapdata_dump.yaml') do
+    it { should exist }
+    its('content') { should include mapdata_dump }
+  end
+end