Get defined examples from response content and make available in templates (!8418) · Merge requests · OpenAPI Tools / openapi-generator

Created by: eNeRGy164

Get defined examples from the response content. Extended the AsciiDoc rendering to show a working implementation.

Should close #6759.

This is my first time in 20 years I've written any Java code. So, please correct me if I have done something stupid.

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.
If contributing template-only or documentation-only changes which will change sample output, build the project beforehand.
Run
```
mvn clean package
./bin/generate-samples.sh
./bin/utils/export_docs_generators.sh
```
to update all Petstore samples related to your fix. 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.
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