add test case for issue #147

Author: rkeytacked

tests/src/test/resources/org/everit/json/schema/issues/issue147/schema.json

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+{"type":"object", "properties": {"prop": {"pattern": "a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"}}}

tests/src/test/resources/org/everit/json/schema/issues/issue147/subject-valid.json

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+{"prop": "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"}