Change default graph image to SVG (#15586)

* Update config_definitions.json

* Update Rrd.php

LibreNMS/Data/Store/Rrd.php

@@ -580,7 +580,7 @@ class Rrd extends BaseDatastore
         }
 
         // if valid image is returned with error, extract image and feedback
-        $image_type = Config::get('webui.graph_type', 'png');
+        $image_type = Config::get('webui.graph_type', 'svg');
         $search = $this->getImageEnd($image_type);
         if (($position = strrpos($process->getOutput(), $search)) !== false) {
             $position += strlen($search);

misc/config_definitions.json

@@ -5970,7 +5970,7 @@
             "type": "boolean"
         },
         "webui.graph_type": {
-            "default": "png",
+            "default": "svg",
             "group": "webui",
             "section": "graph",
             "order": 1,