use CDN to determine availability of newer conda-smithy

[h-vetinari]

The check for being up-to-date with the smithy version seems to go to the package server directly, which leads to the following failure (for the hour or so that the package makes its way through the CDN, during which time the newer version is not actually installable yet!):

RuntimeError: conda-smithy version (3.10.2) is out-of-date (3.10.3) in conda-smithy's environment. Exiting.

That hour is not the most critical thing in the world (though it can be painful when suddenly you cannot rerender just as you need it), but now there was an unlucky confluence of events - basically 3.10.3 was uploaded to the server after conda-forge/status#115 hit the CDN, and until this is resolved, it's impossible to actually install the package and therefore to do any local rerenders.

Ideally, the check should be changed to use the same channel-data as the conda-installer, so that such situations cannot happen again.

[isuruf]

It's not impossible. You can do conda-smithy rerender --no-check-uptodate to make the error go away.

[h-vetinari]

cool, didn't know that option, thanks

[beckermr]

The CDN is an internal detail of anaconda.org. So I'd hesitate to embed its presence in conda-smithy directly.

[isuruf]

Maybe we should add that option to the error message.

[h-vetinari]

Also, --no-check-uptodate does not show up in the conda smithy --help string. I hit this again because with the most recent smithy build being marked as broken, the check fails as well.