The Swift5/Vapor generator doesn't provide a CodingKey for QueryParams, which means they aren't decoded back to their base name. The obvious case is per_page in the spec becoming perPage in the generated code. Without a coding key, it is passed back as perPage in the final query.

(Sorry I didn't bother opening an issue, but this a really small change. Let me know if you want any other formalities followed.)

Technical committee: @jgavris @ehyche @Edubits @jaz-ah @4brunu

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, 5.1.x, 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.