public static IProjectReference AddProjectReference(this ProjectReferencesItemGroupXElement projectReferencesItemGroupXElement, string projectFilePath)
        {
            var hasProjectReferenceAlready = projectReferencesItemGroupXElement.HasProjectReference(projectFilePath);

            if (hasProjectReferenceAlready)
            {
                throw new InvalidOperationException($"Project already has project reference:\n{projectFilePath}");
            }

            var projectReference = ProjectReferenceXElement.New(projectReferencesItemGroupXElement, projectFilePath);

            return(projectReference);
        }
        public static bool HasProjectReference(this ProjectReferencesItemGroupXElement projectReferencesItemGroupXElement, string projectFilePath)
        {
            var hasProjectReference = projectReferencesItemGroupXElement.HasProjectReference(projectFilePath, out _);

            return(hasProjectReference);
        }