Code Insights: Add a click to trigger the disappearance of chart tooltip (fix flaky screenshot test)

Created by: vovakulikov

Closes https://github.com/sourcegraph/sourcegraph/issues/23669

This PR adds two things

1. Adds a click before taking a screenshot to ensure that we didn't trigger any tooltip appearance over the chart
2. Turns off the grid layout animation on mount to avoid random unwanted clicks