Add support for TupleExpressions in CSharpExplodedGraph

[costin-zaharia-sonarsource]

Description

We need to add support for handling TupleExpressions in CSharpExplodedGraph.

Repro steps

Currently the TupleExpressions are just ignored when processing code like:

public class Address
{
    public string Name { get; }

    public string State { get; }

    public void Deconstruct(out string name, out string state) =>
        (name, state) = (Name, State);
}

Additional notes

Once the tuples are supported by CFG and semantic execution we need to update the DeadStores rule (S1854) and remove the check added by #3113.

[andrei-epure-sonarsource]

closing as this will be fixed with the new Roslyn CFG

[pavel-mikula-sonarsource]

@andrei-epure-sonarsource I'd prefer to keep this documented as opened issue until we support it.

[andrei-epure-sonarsource]

@pavel-mikula-sonarsource can we close this now?