Docs for SERVER-35595: Implement the coordinateCommit commands on the shards

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Original Description

Description:

Not sure if we need to document these internal commands, but this change introduces a command in support of the distributed commit protocol.

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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)