OpenApiCustomiser duplicates header fields after browser refresh in springdoc-open-api version >1.6.9

Describe the bug

When OpenApiCustomiser is in use for adding some common header fields to all endpoints, these fields get duplicated in swagger ui and open-api json after browser refresh. This bug is present in versions 1.6.10 and 1.6.11.

To Reproduce
Steps to reproduce the behavior:

• What version of spring-boot you are using?
  2.7.3

• What modules and versions of springdoc-openapi are you using?
  org.springdoc:springdoc-openapi-ui:1.6.11
  org.springdoc:springdoc-openapi-data-rest:1.6.11

• What is the actual and the expected result using OpenAPI Description (yml or json)?

Actual (tested with 1.6.10 and 1.6.11):

"/foo/bar":{"get":{"tags":["Foo"],"operationId":"getBar","parameters":[{"name":"barId","in":"path","required":true,"schema":{"type":"string"}},{"name":"foo","in":"header","description":"foo","required":true,"example":"foo"},{"name":"bar","in":"header","description":"bar","required":true,"example":"bar"},{"name":"foo","in":"header","description":"foo","required":true,"example":"foo"},{"name":"bar","in":"header","description":"bar","required":true,"example":"bar"}},{"name":"foo","in":"header","description":"foo","required":true,"example":"foo"},{"name":"bar","in":"header","description":"bar","required":true,"example":"bar"},{"name":"foo","in":"header","description":"foo","required":true,"example":"foo"},{"name":"bar","in":"header","description":"bar","required":true,"example":"bar"}],"responses" 

..

Expected (this is from version 1.6.9):

"/foo/bar":{"get":{"tags":["Foo"],"operationId":"getBar","parameters":[{"name":"barId","in":"path","required":true,"schema":{"type":"string"}},{"name":"foo","in":"header","description":"foo","required":true,"example":"foo"},{"name":"bar","in":"header","description":"bar","required":true,"example":"bar"}],"responses":

..

• Provide with a sample code (HelloController) or Test that reproduces the problem

Unfortunately, I don't have HelloController at hand right now, so if it's needed please ask. However, there's an example Configuration code:

@Bean
  public OpenAPI fooOpenAPI() {
    return new OpenAPI()
        .info(new Info().title("Foo API Documentation").version("v1.0.0"));
  }

@Bean
public OpenApiCustomiser headerOpenApiCustomiser() {
	return openApi -> openApi.getPaths().values().stream()
	.flatMap(pathItem -> pathItem.readOperations().stream())
	.forEach(operation -> {
	  operation.addParametersItem(
	      new HeaderParameter().required(true).description("foo").name("foo")
		  .example("foo"));
	  operation.addParametersItem(
	      new HeaderParameter().required(true).description("bar").name("bar")
		  .example("bar"));
	});
}


@Bean
public GroupedOpenApi commonApi() {
	return GroupedOpenApi.builder()
	.group("common")
	.addOpenApiCustomiser(headerOpenApiCustomiser())
	.packagesToScan("org.common")
	.build();
}

@Bean
public GroupedOpenApi adminApi() {
	return GroupedOpenApi.builder()
	.group("admin")
	.addOpenApiCustomiser(headerOpenApiCustomiser())
	.packagesToScan("org.admin")
	.build();
}

To reproduce with similar configuration than above:

1. go to swagger-ui with browser
2. open some api-path and check that customised headers are visibile
3. refresh page i.e. press +
4. go back to same path and then there's duplicates
5. by repeating this, you get one new pair of headers on every cycle

Expected behavior

Headers added by customiser are visibile only once all the time

[bnasslahsen]

@alpertti,

This is a duplicate of #1820
You can test the fix with the latest SNAPSHOT