Add expression tests for overloads which take MethodInfo

Such as [this one](https://docs.microsoft.com/en-us/dotnet/api/system.linq.expressions.expression.add?view=netframework-4.8#System_Linq_Expressions_Expression_Add_System_Linq_Expressions_Expression_System_Linq_Expressions_Expression_System_Reflection_MethodInfo_).

This is less important for the code formatters, but it is important for other formatters (#3).