Instead of matching the mediatype against "application/json" it now matches with "application/*json" so vendor specific json mediatypes like "application/vnd.shopping.cart.v2+json" will also be recognized and deserialized. It doesn't map mediatypes to different models.
This would accept malformed mediatypes as well but that doesn't seem harmful.
I'm using a similarly patched template in a project.

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.
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