Background

#6215
Similar (and can be taken together with) #8924
This subitem is focused on unit tests calling using BinaryFormatter:

• Build.UnitTests - testing deserializing exceptions
• Framework.UnitTests - testing deserialization of EventArgs, AssemblyNameEx, CopyOnWriteDictionary
• Removing EnableUnsafeBinaryFormatterSerialization requried bacause of the above unit tests - https://github.com/dotnet/msbuild/blob/main/Directory.Build.props#L46-L52

Since this is non-shipping code, it's not a priority. However it should be easy to get rid of those and hence make usages of BinaryFormatter in our code base scope to the necessary places (e.g. GenerateResource task)`

Suggested approach

Unit tests testing exceptions and EventArgs serialization should be moved to the new serialization mechanisms for those (#8786, #8917), or delete if duplicate with unittests introduced as part of those new serialization mechanisms, or removed if serializing other types (as those should not currently use BinaryFormatter for de/serialization).