skip benchmarks in CI

[kd7lxl]

No need to burn CPU on benchmarks for every CI run.

[codecov]

Codecov Report

Merging #267 (7271b67) into master (07a1ca4) will increase coverage by 0.03%.
The diff coverage is n/a.

❗ Current head 7271b67 differs from pull request most recent head 546567f. Consider uploading reports for the commit 546567f to get more accurate results

@@            Coverage Diff             @@
##           master     #267      +/-   ##
==========================================
+ Coverage   74.54%   74.58%   +0.03%     
==========================================
  Files         162      162              
  Lines       15615    15615              
==========================================
+ Hits        11640    11646       +6     
+ Misses       3172     3165       -7     
- Partials      803      804       +1     

Impacted Files	Coverage Δ
pep/streaming_connection.go	81.57% <0.00%> (+1.97%)	⬆️

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