Remove hacks for 3.6 support

[wyfo]

No description provided.

[codecov-commenter]

Codecov Report

Merging #519 (03c35b4) into master (1eec6ca) will decrease coverage by 0.06%.
The diff coverage is 77.77%.

@@            Coverage Diff             @@
##           master     #519      +/-   ##
==========================================
- Coverage   87.86%   87.79%   -0.07%     
==========================================
  Files          62       62              
  Lines        5678     5679       +1     
  Branches     1093     1236     +143     
==========================================
- Hits         4989     4986       -3     
- Misses        477      480       +3     
- Partials      212      213       +1     

Impacted Files	Coverage Δ
apischema/conversions/visitor.py	95.23% <ø> (ø)
apischema/utils.py	86.97% <0.00%> (ø)
apischema/typing.py	85.58% <75.00%> (ø)
apischema/discriminators.py	95.12% <100.00%> (-0.12%)	⬇️
apischema/graphql/relay/global_identification.py	77.00% <100.00%> (+0.23%)	⬆️
apischema/visitor.py	88.78% <100.00%> (+0.21%)	⬆️
apischema/methods.py	81.81% <0.00%> (-4.55%)	⬇️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.