Create OkHttp on background thread during initialization

[fractalwrench]

Goal

The SDK instantiates OkHttp on the main thread which hit perf. We should load it on a background thread instead.

[priettt]

good catch 🙌

[codecov]

Codecov Report

Attention: Patch coverage is 90.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 84.16%. Comparing base (35e8b52) to head (6f2ad41).

Files with missing lines	Patch %	Lines
.../embracesdk/internal/injection/ConfigModuleImpl.kt	87.50%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@                       Coverage Diff                        @@
##           simplify-behavior-remote-cfg    #1677      +/-   ##
================================================================
+ Coverage                         84.14%   84.16%   +0.02%     
================================================================
  Files                               456      456              
  Lines                             10624    10625       +1     
  Branches                           1603     1603              
================================================================
+ Hits                               8940     8943       +3     
+ Misses                              947      945       -2     
  Partials                            737      737              

Files with missing lines	Coverage Δ
...racesdk/internal/comms/api/EmbraceApiUrlBuilder.kt	94.11% <100.00%> (ø)
...ternal/config/source/CombinedRemoteConfigSource.kt	90.00% <100.00%> (ø)
.../embracesdk/internal/injection/ConfigModuleImpl.kt	84.44% <87.50%> (+0.35%)	⬆️

... and 1 file with indirect coverage changes