chore(docs): add cloud rad

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[codecov]

Codecov Report

Merging #298 into master will decrease coverage by 0.69%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #298      +/-   ##
============================================
- Coverage     79.32%   78.63%   -0.70%     
+ Complexity      319      317       -2     
============================================
  Files            21       21              
  Lines          2892     2892              
  Branches        155      155              
============================================
- Hits           2294     2274      -20     
- Misses          535      537       +2     
- Partials         63       81      +18     

Impacted Files	Coverage Δ	Complexity Δ
...oogle/cloud/pubsub/v1/SubscriptionAdminClient.java	57.65% <0.00%> (-5.41%)	52.00% <0.00%> (ø%)
...a/com/google/cloud/pubsub/v1/TopicAdminClient.java	56.64% <0.00%> (-2.32%)	34.00% <0.00%> (ø%)
...ain/java/com/google/cloud/pubsub/v1/Publisher.java	87.25% <0.00%> (-0.75%)	44.00% <0.00%> (-2.00%)
.../com/google/cloud/pubsub/v1/MessageDispatcher.java	84.87% <0.00%> (-0.49%)	26.00% <0.00%> (ø%)

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