Composite bar charts should be supported

### Description

Composite bar charts (sometimes also call stacked bar charts) are charts where each bar displays multiple data points stacked in a single row or column.
There are situations where no other diagram type can be used to express the intended conclusion. Also the use of 2 diagrams with identical X Axis but different Y axis would not be appropriate. Therefore composite bar charts are rellay needed!

Refer to https://www.goteachmaths.co.uk/composite-bar-charts/

To me it is not quite clear if Mermaid supports this type of diagram at the moment: https://github.com/mermaid-js/mermaid/issues/4269#issuecomment-1868982956