[release/9.0-staging] Don't scaffold NonNullableConventionState annotation

[AndriySvyryd]

Fixes #34996
Port of #35020

Description

NonNullableConventionBase convention adds an annotation to the model containing a cached NullabilityInfoContext to be used during model building. Usually, it's removed before the model is finalized, but in certain cases another convention can request it during finalization after the cache is removed causing the annotation to be added back to the model.

Customer impact

An exception is thrown when adding a new migration or a compiled model for affected models (mostly with types containing a field that's a primitive collection). There is workaround via model configuration, but it's usually not practical because the exception doesn't provide any clues on what property caused it:

System.InvalidOperationException: Cannot scaffold C# literals of type 'System.Reflection.NullabilityInfoContext'. The provider should implement CoreTypeMapping.GenerateCodeLiteral to support using it at design time.

How found

Multiple customer reports on 8 and 9.

Regression

Yes, from 7, but started affecting even more models in 9.

Testing

Test added

Risk

Low.