Thanks to  SERVER-28943 shards now retry non-write commands on stale exception.
This is done unconditionally even if the exception is indicating that the router was stale.

Once database and collection version will be truly comparable (SERVER-52587) we can conditionally refresh and retry the command only if "requiredVersion (Router) > wantedVersion (Shard)".

This new behavior should be either addressed once 5.0 becomes last-lts or should be guarded by an FCV flag in order to be sure that we are on a binary version that uses truly comparable database and collection versions.

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There is a TODO in the codebase referencing a resolved ticket which is assigned to you.

Please follow this link to see the lines of code referencing this resolved ticket:
https://github.com/mongodb/mongo/search?q=SERVER-52784&type=Code

The next steps for this ticket are to either remove the outdated TODO or follow the steps in the TODO if it is correct. If the latter, please update the summary and description of this ticket to represent the work you're actually doing.