Convert all solution files to `.slnx` format · castleproject/Core@18d5ea7

src/Castle.Core/DynamicProxy/Generators/Emitters/ClassEmitter.cs#L198

'FieldAttributes.NotSerialized' is obsolete: 'Formatter-based serialization is obsolete and should not be used.' (https://aka.ms/dotnet-warnings/SYSLIB0050)

src/Castle.Core/Core/Logging/LoggerException.cs#L35

'Exception.Exception(SerializationInfo, StreamingContext)' is obsolete: 'This API supports obsolete formatter-based serialization. It should not be called or extended by application code.' (https://aka.ms/dotnet-warnings/SYSLIB0051)

src/Castle.Core/Core/Resource/ResourceException.cs#L35

'Exception.Exception(SerializationInfo, StreamingContext)' is obsolete: 'This API supports obsolete formatter-based serialization. It should not be called or extended by application code.' (https://aka.ms/dotnet-warnings/SYSLIB0051)

src/Castle.Core/DynamicProxy/DynamicProxyException.cs#L37

'Exception.Exception(SerializationInfo, StreamingContext)' is obsolete: 'This API supports obsolete formatter-based serialization. It should not be called or extended by application code.' (https://aka.ms/dotnet-warnings/SYSLIB0051)

src/Castle.Core/DynamicProxy/Generators/Emitters/SimpleAST/IfNullExpression.cs#L28

Cannot convert null literal to non-nullable reference type.

src/Castle.Core/DynamicProxy/Generators/Emitters/ClassEmitter.cs#L47

'TypeAttributes.Serializable' is obsolete: 'Formatter-based serialization is obsolete and should not be used.' (https://aka.ms/dotnet-warnings/SYSLIB0050)

src/Castle.Core/DynamicProxy/Internal/TypeUtil.cs#L142

Dereference of a possibly null reference.

src/Castle.Core/DynamicProxy/Generators/Emitters/SimpleAST/IfNullExpression.cs#L28

Cannot convert null literal to non-nullable reference type.

src/Castle.Core/DynamicProxy/Internal/TypeUtil.cs#L142

Dereference of a possibly null reference.

src/Castle.Core/DynamicProxy/Generators/Emitters/SimpleAST/IfNullExpression.cs#L28

Cannot convert null literal to non-nullable reference type.