Add curl-multi tests

[matyhtf]

No description provided.

[codecov]

Codecov Report

Merging #4121 (f6931e5) into master (a762d24) will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4121      +/-   ##
==========================================
- Coverage   48.81%   48.77%   -0.05%     
==========================================
  Files          71       71              
  Lines       14271    14271              
==========================================
- Hits         6966     6960       -6     
- Misses       7305     7311       +6     

Impacted Files	Coverage Δ
src/protocol/base.cc	63.15% <0.00%> (-1.98%)	⬇️
src/network/client.cc	46.56% <0.00%> (-0.45%)	⬇️

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