Revert "[Fixes #86] Close the HTTP pool when service is stopped."

[glyph]

Reverts #140

Fixes #154

[codecov]

Codecov Report

Merging #155 into master will increase coverage by 0.73%.
The diff coverage is 100%.

@@           Coverage Diff            @@
##           master   #155      +/-   ##
========================================
+ Coverage   99.26%   100%   +0.73%     
========================================
  Files          27     27              
  Lines        2044   2000      -44     
  Branches      179    173       -6     
========================================
- Hits         2029   2000      -29     
+ Misses         11      0      -11     
+ Partials        4      0       -4

Impacted Files	Coverage Δ
src/txacme/testing.py	100% <ø> (+3.87%)	⬆️
src/txacme/client.py	100% <100%> (+1.85%)	⬆️
src/txacme/test/test_service.py	100% <100%> (ø)	⬆️
src/txacme/test/test_client.py	100% <100%> (ø)	⬆️
src/txacme/endpoint.py	100% <100%> (ø)	⬆️
src/txacme/test/test_endpoint.py	100% <100%> (ø)	⬆️
src/txacme/service.py	100% <100%> (ø)	⬆️
src/txacme/test/test_challenges.py	100% <0%> (+0.94%)	⬆️
src/txacme/challenges/__init__.py	100% <0%> (+28.57%)	⬆️

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