throw error when rng sampler is fed empty array

[Moelf]

fix #46272

[rikhuijzer]

Shouldn't there be a test?

[rfourquet]

Note that rand(()) would still throw the same "range must be non-empty" error. What about changing the existing wording to "collection must be non-empty", which will still be correct for ranges, and will be identical to the message for empty dicts and sets. (Also it will avoid to make this check twice, although the cost is probably negligible).

[ViralBShah]

@rfourquet Please merge whenever you think ok.

[rfourquet]

LGTM, can you check the CI errors are all unrelated?

[Moelf]

I think so, purely because how unreliable our CI is