Add __init_subclass__ to the methods order

[Bobronium]

Add __init_subclass__ to WPS338 order.

New allowed methods order:

• __init_subclass__
• __new__
• __init__
• __call__
• __await__

Checklist

• I have double checked that there are no unrelated changes in this pull request (old patches, accidental config files, etc)
• I have created at least one test case for the changes I have made
• I have updated the documentation for the changes I have made
• I have added my changes to the CHANGELOG.md

Related issues

Closes #2410

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[sobolevn]

Thank you!

[codecov]

Codecov Report

Merging #2411 (3786a48) into master (3daaea4) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master     #2411   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          120       120           
  Lines         6408      6408           
  Branches      1445      1445           
=========================================
  Hits          6408      6408           

Impacted Files	Coverage Δ
wemake_python_styleguide/violations/consistency.py	100.00% <ø> (ø)
wemake_python_styleguide/visitors/ast/classes.py	100.00% <ø> (ø)

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