DEP: set upper bound on numpy requirement (7.2.x) - #19233

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failures on oldestdeps are extremely confusing. Trying to remove the warning filter and see where things go.

seems like we still need to add version-dependent pathes in tests for the backport branch. Working on it.

looks like none of it is trivial, unfortunately, so to avoid further delays, I'll undraft this now: it is already solving the problem it is aimed to resolve, but I can't promise that other problems will be solved too at the moment.

@saimn , are we merging this first before kinda-backporting #19267 ?

@pllim - Fine with me.