fix(flowchart-v2): fix arrowMarkerAbsolute=true

The if-check for arrowMarkerAbsolute in the flowchart-v2 code is in
dagre-wrapper. Unfortunately, I can't seem to find a way to find the
local conf (e.g. the one set via `flowRenderer.setConf()`, so instead
I'm using global mermaid config from `src/config`.

Flowchart v1 arrowMarkerAbsolute=true is still broken, but I'm not
really sure how to fix that.

src/dagre-wrapper/edges.js

@@ -472,7 +472,8 @@ export const insertEdge = function (elem, e, edge, clusterDb, diagramType, graph
   // });
 
   let url = '';
-  if (getConfig().state.arrowMarkerAbsolute) {
+  // // TODO: Can we load this config only from the rendered graph type?
+  if (getConfig().flowchart.arrowMarkerAbsolute || getConfig().state.arrowMarkerAbsolute) {
     url =
       window.location.protocol +
       '//' +