Revert "[chore] change the way we unmarshal the config in tests"

[atoulme]

Reverts #9765

We need to revert those changes as contrib has issues with them in isolation from #9750.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.99%. Comparing base (eb5d2b9) to head (1fe9ed3).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #9771   +/-   ##
=======================================
  Coverage   90.99%   90.99%           
=======================================
  Files         353      353           
  Lines       18635    18635           
=======================================
  Hits        16957    16957           
  Misses       1352     1352           
  Partials      326      326           

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[codeboten]

Should this revert not address these errors:

Error: ../../receiver/opencensusreceiver/factory.go:54:37: cannot use rCfg.NetAddr.Transport (variable of type confignet.TransportType) as string value in argument to newOpenCensusReceiver

[dmitryax]

Should this revert not address these errors:

It should not. That one is part of #9385. I belive @TylerHelmuth is trying to update core dependency in contrib to fix it. and this is blocking it.