Regression: 2.1.26 fails on any header with a `style` property

[Mahoney]

Regression, worked in 2.1.25.

The following OpenAPI:

openapi: 3.1.0
info:
  title: Example
  version: 1.0.0

servers:
  - url: https://api.example.com

paths:
  /foo:
    get:
      description: Demonstrate the issue
      responses:
        "204":
          description: Demonstrate the issue
          headers:
            RateLimit:
              style: simple

Fails when passed to the following code:

SwaggerParseResult swaggerParseResult = new OpenAPIV3Parser()
    .readContents(
        "",
        null,
        new ParseOptions(),
        null
    );
assert swaggerParseResult.getOpenAPI() != null;
assert swaggerParseResult.getMessages().isEmpty();

swaggerParseResult.getOpenAPI() returns null and swaggerParseResult.getMessages() returns one element, Cannot invoke "String.equals(Object)" because "value" is null.

[Mahoney]

Suspect #2164 is the cause of the problem

[alexisnouvel]

We have the same issue, it should be fixed by that PR: #2166

[frantuma]

Thanks for reporting this, fixed in #2166