Migrate to `cs{r,c}_array` internally/externally

[ilan-gold]

We should move towards cs{r,c}_array for the next minor release. This means a few things:

1. https://anndata.readthedocs.io/en/stable/generated/anndata.settings.html#anndata.settings.use_sparse_array_on_read turn this setting on
2. Inside anndata.concat, create cs{r,c}_arrays by default (and anywhere else that they might be created)
3. Update all of our tests to migrate to csr_array for construction of AnnDatas, comparison etc.
4. Push out the change on all channels to inform people of what is coming

See #2476 for where this is beginning to cause issues