Temporarily disable CA1852 for top-level statements

As mentioned in the previous commit, .NET 7 includes a new analyzer [1]
that checks for internal types that can be sealed.

Unfortunately that analyzer is currently generating false positives for
generated `Program` classes [2] and therefore has to be suppressed
manually.

A fix [3] has already been committed to the Roslyn Analyzers repo so we
should be able to remove this suppression once that fix has made its way
into an SDK update.

[1] dotnet/roslyn-analyzers#5594
[2] dotnet/roslyn-analyzers#6141
[3] dotnet/roslyn-analyzers#6278

src/Buttercup.Web/Program.cs

@@ -16,6 +16,8 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Razor;
 
+#pragma warning disable CA1852
+
 var builder = WebApplication.CreateBuilder(args);
 
 var isDevelopment = builder.Environment.IsDevelopment();