docs: improve doctests for ndarray instances in blas/ext/base/ndarray/dcusumkbn2
#7630
| Job | Run time |
|---|---|
| 5s | |
| 5s |
blas/ext/base/ndarray/dcusumkbn2
#7630
| Job | Run time |
|---|---|
| 5s | |
| 5s |