prometheus: update to 2.43.0 and test stringlabels

https://github.com/prometheus/prometheus/releases/tag/v2.43.0%2Bstringlabels

prometheus/map.jinja

 {% set prometheus = salt['grains.filter_by']({
     'default': {
-      'release': '2.42.0',
+      'release': '2.43.0+stringlabels',
       'alertmanager_release': '0.25.0',
       'node_exporter_release': '1.5.0',
     }