Add agent version to CHANGELOG template

[salonichf5]

Cherry-pick commit into release-2.0 branch

[sjberman]

This was already done: #3474.

We just need to cherrypick the agent version update.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.74%. Comparing base (15b7946) to head (fc18a1a).

Additional details and impacted files

@@               Coverage Diff               @@
##           release-2.0    #3490      +/-   ##
===============================================
- Coverage        86.78%   86.74%   -0.04%     
===============================================
  Files              127      127              
  Lines            15079    15079              
  Branches            62       62              
===============================================
- Hits             13087    13081       -6     
- Misses            1840     1845       +5     
- Partials           152      153       +1     

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[sjberman]

Oh shoot, I linked the wrong PR. This change actually wasn't cherry-picked, my fault.

[salonichf5]

Oh shoot, I linked the wrong PR. This change actually wasn't cherry-picked, my fault.

no worries, I have reopened this