Docs for SERVER-35295: Add total number of committed and aborted transactions to serverStatus

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Original Description

Description:

serverStatus has new fields added to it.

Engineering Ticket Description:

We want to output the total number of committed and aborted transactions in the "transactions" serverStatus section by utilizing the existing metrics tracked in the totalCommitted and totalAborted fields of ServerTransactionsMetrics. We need to add totalCommitted and totalAborted fields to the transactions_stats.idl class, so that we can serialize these counters to the serverStatus output object in the TransactionsSSS::generateSection method. The TransactionsSSS::generateSection method returns a BSON object that goes into the transactions section of the serverStatus output.

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Description

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