[java][Micronaut] generator fixes

[oujesky]

Minor fixes for Micronaut generator:

• fixed hardcoded package name for import
• fixed @Consumes and @Produces annotations
• fixed security schemes pairing when dots (or other "special" char) is present

cc @andriy-dmytruk

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• Run the following to build the project and update samples:

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

  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  For Windows users, please run the script in Git BASH.
• File the PR against the correct branch: master (5.3.0), 6.0.x
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.

[andriy-dmytruk]

Hi @oujesky, all the changes are reasonable and make sense. Thank you for this PR.
Please do run integration tests for micronaut. You can for example use these commands to rebuild and run:

./mvnw clean package -DskipTests
./mvnw package integration-test -P java-micronaut-client -P java-micronaut-server

I have noticed that there are some errors for the generated micronaut client as a sample.
To fix them you will probably need to add this dependency in samples/client/petstore/java-micronuat-client:

  <dependency>
    <groupId>io.micronaut.xml</groupId>
    <artifactId>micronaut-jackson-xml</artifactId>
    <scope>compile</scope>
  </dependency>

The other error I encountered is that xml of empty list gets parsed as [""] (list with empty string). Not sure how to fix that. You can annotate the test with @Ignore for now and write another one that doesn't use an empty list if you don't find another solution.

[wing328]

@oujesky can you please resolve the merge conflicts when you've time?

[andriy-dmytruk]

Note: This and the next test failed because of the issue reported in micronaut-projects/micronaut-jackson-xml#175:
phototoUrls is an empty set, but is deserialized as set with an empty String ([""]). No changes are required on the openapi generator side.

[andriy-dmytruk]

Tested locally. LGTM