[BUG][JavaSpring] description values for @Operation annotation are not generated from OpenAPI definition

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

When I run code generation for a Java Spring Api, the description is missing in the @Operation annotation.

openapi-generator version

The bug occurs with the latest openapi-generator version.

OpenAPI declaration file content or url

The bug can be reproduced for example with this file: https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/test/resources/3_0/java/petstore-group-parameter.yaml

Generation Details

Command to generate the code: java -jar openapi-generator-cli-6.3.0-20221110.220613-11.jar generate -i modules/openapi-generator/src/test/resources/3_0/java/petstore-group-parameter.yaml -g spring -o test

Steps to reproduce

Run the code generation command from above.

Output:

...
    @Operation(
        operationId = "findPetsByStatus",
        summary = "Finds Pets by status",
        tags = { "pet" },
        responses = {
            @ApiResponse(responseCode = "200", description = "successful operation", content = {
                @Content(mediaType = "application/xml", schema = @Schema(implementation = Pet.class)),
                @Content(mediaType = "application/json", schema = @Schema(implementation = Pet.class))
            }),
            @ApiResponse(responseCode = "400", description = "Invalid status value")
        },
        security = {
            @SecurityRequirement(name = "petstore_auth", scopes={ "read:pets" })
        }
    )
...

Expected output:

...
    @Operation(
        operationId = "findPetsByStatus",
        summary = "Finds Pets by status",
        description = "Multiple status values can be provided with comma separated strings",
        tags = { "pet" },
        responses = {
            @ApiResponse(responseCode = "200", description = "successful operation", content = {
                @Content(mediaType = "application/xml", schema = @Schema(implementation = Pet.class)),
                @Content(mediaType = "application/json", schema = @Schema(implementation = Pet.class))
            }),
            @ApiResponse(responseCode = "400", description = "Invalid status value")
        },
        security = {
            @SecurityRequirement(name = "petstore_auth", scopes={ "read:pets" })
        }
    )
...

Related issues/PRs

The bug has already been reported with the closed issue https://github.com/OpenAPITools/openapi-generator/issues/11779, but the fix was not correct as mentioned in the discussion.

Suggest a fix

PR with a fix: https://github.com/OpenAPITools/openapi-generator/pull/13995

Start by running the generation command against modules/openapi-generator/src/test/resources/3_0/java/petstore-group-parameter.yaml and compare the Spring output with the expected @Operation annotation. Review the related closed issue 11779 and pull request 13995; done means the generated annotation includes the OpenAPI operation description.