Added strict validation because null can implicitly convert to zero, …

[kolodkinvalentin]

…and that didn't work for enums containing zero.

[wol-soft]

Hi, thanks for the contribution. Can you add a test case for the described behaviour? It belongs here https://github.com/wol-soft/php-json-schema-model-generator/blob/master/tests/Objects/EnumPropertyTest.php

[coveralls]

Pull Request Test Coverage Report for Build 10738122307

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 98.848%

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Totals
Change from base Build 10451489220:	0.0%
Covered Lines:	3003
Relevant Lines:	3038

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💛 - Coveralls

[kolodkinvalentin]

Hi!, I tried adding a simple test for the successful creation of an object with an optional field. I also added a zero value to the UntypedEnumProperty.json file. If we remove yesterday's changes on AbstractPropertyProcessor, the tests will fail with errors.

[wol-soft]

Thanks! Great contribution! I'll tag a new patch version including the change