Refactor validator to func

[manycoding]

No description provided.

[codecov]

Codecov Report

Merging #107 into _key will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##             _key     #107      +/-   ##
==========================================
+ Coverage   79.07%   79.08%   +<.01%     
==========================================
  Files          23       22       -1     
  Lines        1606     1597       -9     
  Branches      278      277       -1     
==========================================
- Hits         1270     1263       -7     
+ Misses        290      289       -1     
+ Partials       46       45       -1

Impacted Files	Coverage Δ
src/arche/rules/json_schema.py	100% <100%> (ø)	⬆️
src/arche/tools/schema.py	88.17% <100%> (+10.17%)	⬆️

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[ivankivanov]

What is the reason for this refactoring?

[manycoding]

@ivankivanov As always, code readability. If I see something which can be written simpler I rewrite it, and by doing this I keep the code up-to-date.