use correct namespace in cuio code examples

[cwharris]

use correct namespace in cuio reader/writer code examples

[karthikeyann]

check all files for similar change in this PR.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (branch-21.10@eacc24b). Click here to learn what that means.
The diff coverage is n/a.

❗ Current head da19c58 differs from pull request most recent head 98cc658. Consider uploading reports for the commit 98cc658 to get more accurate results

@@               Coverage Diff               @@
##             branch-21.10    #9037   +/-   ##
===============================================
  Coverage                ?   10.70%           
===============================================
  Files                   ?      114           
  Lines                   ?    18708           
  Branches                ?        0           
===============================================
  Hits                    ?     2003           
  Misses                  ?    16705           
  Partials                ?        0           

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[ttnghia]

Please add PR description 😃

[cwharris]

@ttnghia I was under the impression the title of the PR becomes part of the commit message... There's not a lot to say here that isn't said in the title.

[cwharris]

@gpucibot merge