chore: move readme changes on stackdriver examples

[mutianf]

Move the changes in #613 to the correct file.

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Fixes #<issue_number_goes_here> ☕️

[codecov]

Codecov Report

Merging #617 (cfb76d8) into master (3e8af74) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #617   +/-   ##
=========================================
  Coverage     81.71%   81.71%           
  Complexity     1156     1156           
=========================================
  Files           110      110           
  Lines          7214     7214           
  Branches        377      377           
=========================================
  Hits           5895     5895           
  Misses         1119     1119           
  Partials        200      200           

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