MNT: Numpy 2.0 removals from ndarray class

[ksunden]

PR summary

xref numpy/numpy#24682

Only a handful of lines, and mostly in tests/relatively unused utility functions like rgb_to_hsv, but still something that should be addressed.

PR checklist

• [n/a] "closes #0000" is in the body of the PR description to link the related issue
• [n/a] new and changed code is tested
• [n/a] Plotting related features are demonstrated in an example
• [n/a] New Features and API Changes are noted with a directive and release note
• [n/a] Documentation complies with general and docstring guidelines

[QuLogic]

I'm not sure if it matters too much, but the upstream PR does do the view before byteswap.

[ksunden]

I'm pretty sure those are equivalent; byteswap will incur a copy (unless inplace=True) and view is just a view, but whether the copy comes before or after the view doesn't really matter.