[Feature request] Support RegularExpressionAttribute for string collections.

[Drake53]

Currently when using JSchemaGenerator, if a property is of type ICollection<string> (for example List<string>), the [RegularExpressionAttribute] is ignored, for example the following class:

public class MyClass
{
  [RegularExpression("^[A-Z]+$")]
  public List<string> PropertyName { get; set; }
}

Generates the following schema:

{
  "$schema": "...",
  "type": "object",
  "properties": {
    "PropertyName": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  }
}

It would be nice if there was built-in support for this, so the schema would be generated as follows:

{
  "$schema": "...",
  "type": "object",
  "properties": {
    "PropertyName": {
      "type": "array",
      "items": {
        "type": "string",
        "pattern": "^[A-Z]+$"
      }
    }
  }
}

The same probably applies to [StringLengthAttribute] as well, though I haven't tested this.

As a workaround, a custom JSchemaGenerationProvider implementation can be used.