[Micronaut] [Server] Add support for security roles with extension

Created by: andriy-dmytruk

Added ability to apply security roles on operations with the x-roles extension as in this example:

    post:
      tags: [books]
      summary: Create a new book
      operationId: createBook
      parameters:
        - {name: bookName, in: path, required: true, schema: {type: string}}
      requestBody:
        content:
          application/json: { schema: { $ref: "#/components/schemas/Book" } }
      responses:
        '200':
          description: success
      x-roles: ["admin"]

It will be added with Micronaut's @Secured annotation. Also supports isAuthorized(), isAnonymous() and denyAll() values that will be converted to Micronaut constants.

I ran the following to validate build:

./mvnw clean package
./bin/generate-samples.sh
./bin/utils/export_docs_generators.sh
./bin/meta-codegen.sh

./mvnw integration-test -P "java-micronaut-client,java-micronaut-server"

@wing328

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