swagger-codegen 3.0.19 fail with NPE for jaxrs-jersey when use securitySchemes

Description

I upgraded from Swagger 2.0 to OpenApi 3.x and ran into issues around Security Schemes.
I defined securitySchemes bearer but it is failing with NPE when generating code around generators.DefaultCodegenConfig.fromSecurity .
I recreated the issue with a very simple YAML file.
It generates code fine from swagger UI hence something to do with code-gen used from CLI.

Swagger-codegen version

3.0.19 and 3.0.20 Worked fine

Swagger declaration file content or url

Command line used for generation

swagger-codegen generate -i provided_swagger.yaml -l jaxrs-jersey

Steps to reproduce

swagger-codegen generate -i provided_swagger.yaml -l jaxrs-jersey

Related issues/PRs

Suggest a fix/enhancement

---

Suspect schemeDefinition.getScheme() is returning Null instead of Bearer for some reason.
src/main/java/io/swagger/codegen/v3/generators/DefaultCodegenConfig.java

else if (SecurityScheme.Type.HTTP.equals(schemeDefinition.getType())) {
if ("bearer".equalsIgnoreCase(schemeDefinition.getScheme())) {
codegenSecurity.getVendorExtensions().put(CodegenConstants.IS_BEARER_EXT_NAME, Boolean.TRUE);
final Map<String, Object> extensions = schemeDefinition.getExtensions();
if (extensions != null && extensions.get("x-token-example") != null) {
final String tokenExample = extensions.get("x-token-example").toString();
if (StringUtils.isNotBlank(tokenExample)) {
codegenSecurity.getVendorExtensions().put("x-token-example", tokenExample);
}
}
}

---

security_issue_log.txt
openapi_security_issue.yaml.txt

Start by reproducing the failure with the provided openapi_security_issue.yaml.txt and the swagger-codegen generate command using jaxrs-jersey. Inspect generators/DefaultCodegenConfig.java around fromSecurity and schemeDefinition.getScheme(); done means the same OpenAPI 3 security scheme generates successfully without an NPE.