Plotting color instead of by var in table and alpha not respected

[melonora]

In the aggregation notebook in spatialdata-notebooks we color shapes at some point by aggregated points of gene b. However, it seems b is interpreted as color blue and the values in the table are ignored for the fill color:

Also one can see that the alpha is ignored. This is also the case currently in the notebook version in the scverse docs.

[melonora]

Of note, I am testing the multi table branch of spatialdata but this did not have an effect on what the table looks like as far as I can tell.

[melonora]

Particularly this part of the code in render_shapes is the problem:

        elif colors.is_color_like(color):
            logger.info("Value for parameter 'color' appears to be a color, using it as such.")
            color = color
            col_for_color = None

Ultimately it would only be the case if genes were called like this so I think we should not fix it here, but rather change the names of genes in the example.