Don't capture mouse within tip labels

Fixes a bug whereby branch hover/click-events didn't work because the
tip label captured the mouse, which is very common on tangletrees
(because the text starts to the right of the tip and thus always
obscures branches). Note that the branch labels already had this setting.

src/components/tree/phyloTree/labels.js

@@ -39,6 +39,7 @@ export const updateTipLabels = function updateTipLabels(dt) {
         .text((d) => tLFunc(d))
         .attr("class", "tipLabel")
         .style("font-size", fontSize.toString() + "px")
+        .style("pointer-events", "none")
         .style("visibility", (d) => (d.visibility === NODE_VISIBLE ? "visible" : "hidden"));
     }, dt);
   }