feat(cosmo): complete the keyword argument deprecations - #18800

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Does require a changelog. I'll wait until v7.2 is released.

SGTM. I've kept them for all public methods. For private methods passing positional arguments is backwards compatible.

@pllim, Now that v7.2 branch has been made, is it safe to start merging in v8.0 content?

is it safe to start merging in v8.0 content?

Yes, but you should rebase, just to be sure the branch is still OK. Thanks.

@pllim, our pre-commit appears to be broken :(.

GitHub is unstable right now; we just have to wait it out and then you have to retrigger. FYI.

@pllim it stabilized long enough for this to pass :).

I'll give @neutrinoceros a chance to review also since he had comments above. Thanks!

@neutrinoceros this PR hasn't changed much since your last review. I added the .. versionchanged and a changelog. :).

@neutrinoceros, maybe a good follow up to this PR would be moving the decorator into astropy.utils ? I don't think it's used in cosmology anymore.

Sorry for dropping the ball. LGTM now. Yes, we can move this code next time we need it. If it doesn't find a new use case in astropy 8.0, we should probably just remove it entirely

I opened #18951 to follow up.