feat(map): generate a YAML file to validate map.jinja

We provide a new `_mapdata` state which generate a
`/tmp/salt_mapdata_dump.yaml` to be validated by `Inspec`.

openssh/_mapdata/_mapdata.jinja

@@ -0,0 +1,13 @@
+# yamllint disable rule:indentation rule:line-length
+# {{ grains.get('osfinger', grains.os) }}
+---
+{#- use salt.slsutil.serialize to avoid encoding errors on some platforms #}
+{{ salt['slsutil.serialize'](
+     'yaml',
+     map,
+     default_flow_style=False,
+     allow_unicode=True,
+   )
+   | regex_replace("^\s+'$", "'", multiline=True)
+   | trim
+}}