Added support for openapi-normalizer in the online version.

[GeorgeFkd]

Added support for openapi-normalizer in the online version with a minimal test.
To fix #18677.

The changes done are the following:

• Added an openapiNormalizer List argument to the api (if this is not a desired change i can just put it in the options object and just parse the list of strings).
• Wrote the feature in a similar manner as in the generator-cli code.
• Wrote a minimal test that checks that the normalized version code is less (or equal) in size to the not normalized version.

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/configs/*.yaml
  ./bin/utils/export_docs_generators.sh
  

  (For Windows users, please run the script in Git BASH)
  Commit all changed files. [In my case it did not create any changes]
  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*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
• File the PR against the correct branch: master (upcoming 7.6.0 minor release - breaking changes with fallbacks), 8.0.x (breaking changes without fallbacks)
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.