Clicking on cell types on the wheel is not working after we searched for a species

[lingyun1010]

Given the search term is Mus musculus, https://wwwdev.ebi.ac.uk/gxa/sc/search/metadata/Mus%20musculus.

The cell type wheel is not homogeneous, i.e., one node has four levels and the others only have three levels.

In our implementation senario, we always consider to trigger a gene expression search on the level 4.

          point: {
            events: {
              click: function () {
                if (this.node.level === 4) {
                  const species = _.split(this.id, `#`, 1)
                  props.onCellTypeWheelClick(this.name, species[0], this.experimentAccessions)
                }
              }
            }
          },

So, in this case, if the node lymphocyte is clicked, it requested gene expression from endpoints as usual, but the others are not.

It is a bit hard to say now, we need to confirm with curators to check what to do,

1. Species metadata search is allowed?
2. 4 levels and uneven levels in the cell type wheel is allowed?
3. Gene expression search from level 3 in the species-centred wheel is enabled?

[lingyun1010]

Based on the team meeting discussion, we have the following conclusions:

1. Species search is allowed.
2. The cell type wheel should be homogeneous and there is a bug data in this example search, https://wwwdev.ebi.ac.uk/gxa/sc/search/metadata/Mus%20musculus. where we have a four level, from Homo sapiens section, which should not be included in the Mus musculus search
3. Level 3 should be the gene expression search level for species-centred wheel.