Configures axis titles.
Usually, an axis title displays units of measurement for values displayed by an axis. However, you can display any needed text in the axis title.
The commonAxisSettings.title object, which is described here, specifies common settings for all axis titles in the chart. To configure only the axis title that belongs to a particular axis, use the following objects.
Axis-specific settings override common settings.
Adds a pixel-measured empty space between the axis title and axis labels.