Link line is overlapping with text

I am using this sample Regrouping Tree View | GoJS,

I’d like to know the best way to avoid overlapping text with link. You can check below attached image for your ref.

I have added this code but its not helping me to avoid overlapping
this.$options.mySimpleDiagram.linkTemplate = $(
routing: go.Link.AvoidsNodes,
relinkableFrom: true,
relinkableTo: true,
toShortLength: 4,
fromShortLength: 4,
curve: go.Link.Bezier,
adjusting: go.Link.Stretch,
new go.Binding(“fromSpot”, “fromSpot”, go.Spot.Right),
new go.Binding(“toSpot”, “toSpot”, go.Spot.Right),
$(go.Shape, {
toArrow: “OpenTriangle”,
strokeWidth: 2,
fill: “#666666”,
stroke: “#666666”,

    $(go.Shape, { toArrow: "Standard", fill: "#666666", stroke: "#666666" })

Please give me solution for this

I think the problem is that there isn’t enough room for link routes not to overlap with the nodes and groups that are so close to the connected nodes. Increase the GridLayout.spacing from 4x4 to 20x20 or larger.