Use readonly

Author: commonsensesoftware

src/AspNetCore/OData/test/Asp.Versioning.OData.Tests/OData/ModelConfigurationFeatureProviderTest.cs

@@ -41,7 +41,7 @@ namespace ModelConfigurations
     {
         internal struct ValueTypeModelConfiguration : IModelConfiguration
         {
-            public void Apply( ODataModelBuilder builder, ApiVersion apiVersion, string routePrefix ) { }
+            public readonly void Apply( ODataModelBuilder builder, ApiVersion apiVersion, string routePrefix ) { }
         }
 
         internal sealed class PrivateModelConfiguration : IModelConfiguration

src/Common/src/Common.Backport/HashCode.cs

@@ -3,6 +3,7 @@
 #pragma warning disable IDE0079
 #pragma warning disable IDE0007 // Use implicit type
 #pragma warning disable IDE0079 // Remove unnecessary suppression
+#pragma warning disable IDE0251 // Make member 'readonly'
 #pragma warning disable SA1108 // Block statements should not contain embedded comments
 #pragma warning disable SA1132 // Do not combine fields
 #pragma warning disable SA1200 // Using directives should be placed correctly