add date time to trace (release 6.2)

[sfc-gh-dyoungworth]

This PR is resolves #...

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[sfc-gh-dyoungworth]

This is the same change cherry-picked from my PR to master: #3985

Since there is no joshua for 6.2, I ran 10K correctness against the master branch with no errors.

Ideally this should go into 6.2, but I'm happy to push it to 6.3 if we think its not worth the risk

[sfc-gh-tclinkenbeard]

Nit: This doesn't need to be exposed in the header file.

[sfc-gh-dyoungworth]

Also tested the 6.2 build locally to make sure the DateTime looked correct outside of simulation