/// <summary>
 /// Adds the partial modifier to a class declaration and returns the new declaration.
 /// </summary>
 /// <param name="syntax">The syntax.</param>
 /// <returns></returns>
 internal static ClassDeclarationSyntax AddPartial(this ClassDeclarationSyntax syntax)
 => syntax.AddModifier(SyntaxFactory.Token(SyntaxKind.PartialKeyword).WithTrailingTrivia(SyntaxFactory.Space));