Fix required in composition

[sebastianmika]

This would close #14 and #15 at the expense of only being able to validate required and readOnly/writeOnly combinations when the required is defined on the same schema as the readOnly/writeOnly property.

Personally I would find that more balanced, esp. since readOnly and writeOnly seem to have been dropped from the latest 3.1.0 OpenAPI specs (cf. OAI/OpenAPI-Specification#1622).

That being said, it might even be more consequent to just resort back to the jsonschema.validators.required.

[codecov]

Codecov Report

Merging #16 (b106d9c) into master (185112b) will increase coverage by 5.13%.
The diff coverage is 85.71%.

@@            Coverage Diff             @@
##           master      #16      +/-   ##
==========================================
+ Coverage   59.89%   65.02%   +5.13%     
==========================================
  Files           6        6              
  Lines         182      183       +1     
==========================================
+ Hits          109      119      +10     
+ Misses         73       64       -9     

Impacted Files	Coverage Δ
openapi_schema_validator/_validators.py	50.00% <85.71%> (+16.10%)	⬆️

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[sebastianmika]

Hi - any chance to get this merged and if yes, any ETA? Else I would consider moving to a private fork, because the issue described here and in #14 is posing regular issues in our production systems.

[p1c2u]

LGTM