JetBrains HTTP Client - Adds support for query and header params and env file

This aims to be a fix for #18244. Still WIP. Will update when ready.

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[x] 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.
[x] 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
```
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OpenAPITools / openapi-generator