cleanup: remove obsolete mesos configuration

[dgrove-oss]

Remove bits of mesos code missed in #5133

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.61%. Comparing base (4e25ada) to head (f3d380b).
⚠️ Report is 185 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #5144       +/-   ##
===========================================
+ Coverage   43.94%   74.61%   +30.67%     
===========================================
  Files         231      231               
  Lines       12806    12803        -3     
  Branches      503      501        -2     
===========================================
+ Hits         5627     9553     +3926     
+ Misses       7179     3250     -3929     

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