Remove some debug print statements from gtests

[davidwendt]

While working on #8883 I found some print statements that were a bit annoying while trying to narrow done the cuda-memcheck errors. This PR removes them. I don't think any of these are hard to recode if needed for a specific debug session but I feel they should not be inflicted on developers who are debugging other issues.

[codecov]

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@@               Coverage Diff               @@
##             branch-21.10    #9048   +/-   ##
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  Coverage                ?   10.65%           
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  Files                   ?      114           
  Lines                   ?    19080           
  Branches                ?        0           
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  Hits                    ?     2033           
  Misses                  ?    17047           
  Partials                ?        0           

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[vuule]

@gpucibot merge