Fix gitGraph findLane function error

findLane may infinite loop after recursive call, then cause RangeError: Maximum call stack size exceeded.

src/diagrams/git/gitGraphRenderer.js

@@ -336,7 +336,7 @@ const findLane = (y1, y2, _depth) => {
     return candidate;
   }
   const diff = Math.abs(y1 - y2);
-  return findLane(y1, y2 - diff / 5, depth);
+  return findLane(y1, y2 - diff / 5, depth + 1);
 };
 
 /**