refactor(pubsub): modify attributes according to otel spec

[alevenberg]

Changes in open-telemetry/semantic-conventions#545

• Fixes for the publisher
  Publish span
• Remove the link # attribute
• Add a full name topic attribute
• Add a gcp_pubsub attribute
• Change publish to client not producer
  Create span
• Remove topic attribute

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This change is 

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (c5393be) 93.05% compared to head (7768597) 93.05%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #13263   +/-   ##
=======================================
  Coverage   93.05%   93.05%           
=======================================
  Files        2137     2137           
  Lines      186562   186565    +3     
=======================================
+ Hits       173610   173614    +4     
+ Misses      12952    12951    -1     

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