C#: Sync GD with Core

[raulsntos]

• Add overloads to print methods that take a single string.
  • I think using a single string parameter is the most common scenario (we use it like that a lot in the documentation) so avoiding the array allocation should be a big perf improvement.
• Use StringBuilder to append the print parameters.
  • Should result in better performance, but I haven't benchmarked this.
• Remove GD.PrintStack.
  • Users can call GD.Print(System.Environment.StackTrace) directly.
• Remove GD.Str.
  • Users can use $ string interpolation.
• Add exception to GD.Range when step is 0.
  • GDScript version prints an error in this case.
• Add GD.VarToBytesWithObjects and GD.BytesToVarWithObjects.
  • Added to Core in Create Variant built-in functions. #43446.
• Remove optional boolean parameter from GD.VarToBytes and GD.BytesToVar.
  • Removed from Core in Create Variant built-in functions. #43446.
• Move GD.InstanceFromId to Godot.Object.InstanceFromId.
  • This feels more natural since Godot.Object already contains similar methods (IsInstanceValid and IsInstanceIdValid).
• Add Godot.Object.IsInstanceIdValid.
  • Added to Core in Create Variant built-in functions. #43446.
• Update documentation.

[akien-mga]

Thanks!