v14: JSON schema tool improvements (#16035)

* Use require modifier instead of setting null-suppressed default values

* Only remove read-only properties when IgnoreReadOnlyProperties is set

* Obsolete UmbracoPath property and remove work-around for obsolete setter

tools/Umbraco.JsonSchema/Program.cs

@@ -1,5 +1,4 @@
 using CommandLine;
-using Umbraco.Cms.Core.Configuration.Models;
 
 await Parser.Default.ParseArguments<Options>(args).WithParsedAsync(async options =>
 {
@@ -7,8 +6,5 @@ await Parser.Default.ParseArguments<Options>(args).WithParsedAsync(async options
     var jsonSchemaGenerator = new UmbracoJsonSchemaGenerator();
     var jsonSchema = jsonSchemaGenerator.Generate(typeof(UmbracoCmsSchema));
 
-    // TODO: When the UmbracoPath setter is removed from GlobalSettings (scheduled for V12), remove this line as well
-    jsonSchema.Definitions[nameof(GlobalSettings)]?.Properties?.Remove(nameof(GlobalSettings.UmbracoPath));
-
     await File.WriteAllTextAsync(options.OutputFile, jsonSchema.ToJson());
 });