[BUG] [CSharp] Skip model properties in schemas with empty names ""

Bug Report Checklist

• [v] Have you provided a full/minimal spec to reproduce the issue?
• [v] Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?

Not with master, but with the latest released version in npm.

• [v] Have you searched for related issues/PRs?
• [v] What's the actual output vs expected output?

Description

In CSharp code generation, there is a build error in generated code due to model properties with empty names in the schema, like this one "": { "type": "string" } (bad practice, but it is out of my control, I didn't define the json schema, just generating code for it), this would not happen if the code generator just skipped these properties completely.

openapi-generator version

openapi-generator-cli version
Did set selected version to 7.8.0

Steps to reproduce

openapi-generator-cli generate -g csharp --skip-validate-spec  -i https://raw.githubusercontent.com/PagerDuty/api-schema/5d679f79622d30b767c777be5f2e9787ef21e092/reference/REST/openapiv3.json

In the code generated, if you open the Notification.cs file, you will find multiple build errors due to the property code missing the name like this:

• public string { get; set; }
• public Notification(..., string = default(string))
• this. = ;
• sb.Append(" : ").Append().Append("\n");

Suggest a fix

When reading a json schema with empty property names, just show a warning to the console, but skip it during code generation specially when using the flag --skip-validate-spec.

Reproduce the issue with the provided openapi-generator-cli command and inspect the generated Notification.cs file for properties with empty names. Trace how the CSharp generator handles schema properties when --skip-validate-spec is used, then verify that empty-name properties are skipped with a warning and that generated code no longer contains the shown build errors.