Docs for SERVER-33662: Remove deprecated db.eval command

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Original Description

Description:

See SERVER-35847

Engineering Ticket Description:

In MongoDB 3.0 we deprecated the db.eval command (SERVER-17453).

This command has a number of bugs and security issues related to it, and given that it's now been deprecated for several releases, we should remove it in 4.0.

We will likely also need a DOC ticket associated with this, and potentially a CS ticket for our services.

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Description

Scope of changes (files that need work and how much)

Impact to other docs outside of this product

MVP (work and date?)

Resources (e.g. Scope Docs, Invision)