ReferenceV3 resolves incorrect value for schema names that start with Http

[captainsafia]

In ASP.NET Core, there are two types named HttpValidationProblemDetails and HttpProblemDetails that developers can use to return the responses that comply with the ProblemDetails RFC.

The type names are used as the schema IDs in the default implementation of our OpenAPI generation.

This presents an issue with the current logic of the ReferenceV3 property which has a special case around IDs that start with HTTP.

OpenAPI.NET/src/Microsoft.OpenApi/Models/OpenApiReference.cs

Lines 77 to 107 in a457935

	public string ReferenceV3
	{
	get
	{
	if (IsExternal)
	{
	return GetExternalReferenceV3();
	}
	if (!Type.HasValue)
	{
	throw new ArgumentNullException(nameof(Type));
	}
	if (Type == ReferenceType.Tag)
	{
	return Id;
	}
	if (Type == ReferenceType.SecurityScheme)
	{
	return Id;
	}
	if (Id.StartsWith("http", StringComparison.OrdinalIgnoreCase))
	{
	return Id;
	}
	return "#/components/" + Type.Value.GetDisplayName() + "/" + Id;
	}
	}

The end result being that schema references for these types do not get generated correctly.

We should switch to a more resilient URL check for this case to avoid mishandling schema IDs that are intentionally beginning with Http.

cc: @mikekistler the distinguished bug finder

[baywet]

@captainsafia the simplest fix is probably to example the start with to also check for "://", and duplicate for https. What do you think?
Is this something you'd like to submit a pull request for?