Cleanup warnings: CS0414 (#36950)

* Clean up

* Use #pragma

Content.Server/Maps/MapMigrationSystem.cs

@@ -17,7 +17,9 @@ namespace Content.Server.Maps;
 /// </summary>
 public sealed class MapMigrationSystem : EntitySystem
 {
+#pragma warning disable CS0414
     [Dependency] private readonly IPrototypeManager _protoMan = default!;
+#pragma warning restore CS0414
     [Dependency] private readonly IResourceManager _resMan = default!;
 
     private const string MigrationFile = "/migration.yml";