Network nodes cannot be unselected

[alexmanuele]

Description

There is an app callback that allows you to click nodes in the network plot to highlight them. Clicking highlights the node, all edges connected to the node, and all nodes connected to those edges. However, there is no way to de-select nodes.

The callback is found in app.py and is called highlight_edges

Acceptance Criteria

• The highlight_edges callback is adjusted such that clicking a node that was previously selected returns it to it's default state.