Update cgmanifest to align with the JSON schema

[jeffhandley]

With dotnet/machinelearning#7283, we realized that the cgmanifest.json file was not aligned with the JSON schema. It is using Title case property names but it should be using camelCase property names. See this comment for more detail: dotnet/machinelearning#7283 (comment)

I'm following up by updating each CG manifest in the dotnet org where we had the same issue.

Here's the console app I used to confirm the existing manifest isn't valid against its schema, and the updated one in this PR is valid:

using System;
using System.Net.Http;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using Json.Schema; // Requires package JsonSchema.Net

HttpClient httpClient = new();

string schemaUrl = "https://json.schemastore.org/component-detection-manifest.json";
HttpResponseMessage schemaResponse = await httpClient.GetAsync(schemaUrl);
schemaResponse.EnsureSuccessStatusCode();
string schemaJson = (await schemaResponse.Content.ReadAsStringAsync()).Replace("/draft-04/", "/draft-06/");
JsonSchema schema = JsonSchema.FromText(schemaJson);

string[] manifestUrls = [
    "https://raw.githubusercontent.com/dotnet/icu/refs/heads/dotnet/main/cgmanifest.json",
    "https://raw.githubusercontent.com/jeffhandley/dotnet-icu/refs/heads/jeffhandley/cgmanifest/cgmanifest.json"
];

foreach (var manifestUrl in manifestUrls)
{
    HttpResponseMessage manifestResponse = await httpClient.GetAsync(manifestUrl);
    manifestResponse.EnsureSuccessStatusCode();
    string manifestJson = await manifestResponse.Content.ReadAsStringAsync();

    JsonNode manifest = JsonNode.Parse(manifestJson);

    var result = schema.Evaluate(manifest);
    Console.WriteLine(manifestUrl);
    Console.WriteLine($"Valid: {result.IsValid}");
    Console.WriteLine();
}

Here's the output:

https://raw.githubusercontent.com/dotnet/icu/refs/heads/dotnet/main/cgmanifest.json
Valid: False

https://raw.githubusercontent.com/jeffhandley/dotnet-icu/refs/heads/jeffhandley/cgmanifest/cgmanifest.json
Valid: True

[akoeplinger]

Thank you!