VSSDK006 does not recognize null check in combination with ternary condition

[DmitryGaravsky]

Bug description

A clear and concise description of what the bug is.

• Version of the vssdk-analyzers: 16.3.14
• Analyzer rule: VSSDK006
• Error (exception message, type, and callstack where applicable):

Warning VSSDK006 Check whether the result of GetService calls is null.

To Reproduce

Sample code:

var item = provider.GetService(typeof(EnvDTE.ProjectItem)) as EnvDTE.ProjectItem; // <<< warning here
return (item != null) ? item.ContainingProject : null;

Expected behavior

No error since checking item for null is present.

Additional context

This code works fine:

var item = provider.GetService(typeof(EnvDTE.ProjectItem)) as EnvDTE.ProjectItem; // <<< no warning here
if (item != null)
    return null;
return item.ContainingProject;