[BUG] csharp* should rename `system` components to things that aren't `system`.

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)? (It shows no errors as far as I can tell)
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

When I generate a csharp-netcore solution for https://raw.githubusercontent.com/SpaceTradersAPI/api-docs/main/reference/SpaceTraders.json it generates a class called system - which breaks the entire project, because system should be reserved for the systems system.

openapi-generator version

openapi-generator-cli 6.6.0-SNAPSHOT
commit : ff9b384

OpenAPI declaration file content or url

https://raw.githubusercontent.com/SpaceTradersAPI/api-docs/main/reference/SpaceTraders.json

Generation Details

Steps to reproduce

java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -i https://raw.githubusercontent.com/SpaceTradersAPI/api-docs/main/reference/SpaceTraders.json -g csharp-netcore -o ~/Ship/

Open in your favorite C# editor or even just try to build it.

Related issues/PRs

Not that I know of

Suggest a fix

No idea.

Run the provided openapi-generator-cli command with the linked SpaceTradersAPI specification and the csharp-netcore generator to reproduce the invalid system class. Then trace the csharp-netcore name-generation and reserved-word handling entry points. Done means the generated C# solution builds without the conflicting system component name.