NullReferenceException in Workspace.CollectDataLayoutNodes

[fm-117]

Describe the bug
A NullReferenceException may be thrown by Workspace.CollectDataLayoutNodes method.

To Reproduce
No source code to reproduce.

Expected behavior
No exception.

Technical
See

TypeCobol/TypeCobol.LanguageServer/Workspace.cs

Line 1103 in c1fdd30

Node dataDivision = compilationUnit.TemporaryProgramClassDocumentSnapshot.Root.MainProgram.GetChildren<DataDivision>().FirstOrDefault();

This line should be protected against null values.

How to test automatically
TODO

[fm-117]

Full stacktrace:

   at TypeCobol.LanguageServer.Workspace.CollectDataLayoutNodes(CompilationUnit compilationUnit)
   at TypeCobol.LanguageServer.Workspace.GetDataLayoutAsCSV(CompilationUnit compilationUnit, String separator)
   at TypeCobol.LanguageServer.TypeCobolCustomLanguageServerProtocol.TypeCobolCustomLanguageServer.OnDidReceiveGetDataLayout(GetDataLayoutParams parameter)
   at TypeCobol.LanguageServer.TypeCobolCustomLanguageServerProtocol.TypeCobolCustomLanguageServer.ReceivedGetDataLayoutRequest(RequestType requestType, Object parameters, LSPProfiling lspProfiling)