Code formatting updates (#4502)

* Editorconfig: Add space_before_self_closing setting

This was a difference between the way dotnet-format and Rider format code. See https://www.jetbrains.com/help/rider/EditorConfig_Index.html

* Editorconfig: Keep 4 spaces indentation for Swagger JSON files

They are all formatted that way, let's keep it like that.

* Apply dotnet-format, mostly white-space related changes

BTCPayServer.Client/Models/StoreBaseData.cs

@@ -60,7 +60,7 @@ namespace BTCPayServer.Client.Models
         public NetworkFeeMode NetworkFeeMode { get; set; } = NetworkFeeMode.Never;
 
         public bool PayJoinEnabled { get; set; }
-        
+
         public InvoiceData.ReceiptOptions Receipt { get; set; }