Update chart visualization to fill the panel container

Problem to solve

Currently the LineChart visualization does not fill its panel container's height. This also impacts the ColumnChart visualization.

This is because setting the height: 'auto' on GlChart components does not work and needs to be fixed in GlLineChart: Chart does not fill container heig... (gitlab-ui#2167 - closed).

Proposal

Once GlLineChart: Chart does not fill container heig... (gitlab-ui#2167 - closed) is resolved, update LineChart to fill its container's height.

Implementation plan

Update chart visualizations to fill their container's height.