Fix S2952 FP: Field disposal not recognized for some well known Dispose patterns

[martin-strecker-sonarsource]

Follow up to #6229

#6229 (comment)

Description

S2952 recognizes this pattern:

 public void Cleanup() => fs.Dispose(); // Compliant: disposal is taking place in Dispose() too
 public void Dispose() => fs.Dispose();

These comparable constructs are not detected

1. Disposed in virtual Dispose(bool disposing) of the dispose pattern

 public void Cleanup() => fs.Dispose(); // FP
 public void override Dispose(bool disposing) => fs.Dispose(); 

2. Disposed in DisposeAsync

 public void Cleanup() => fs.Dispose(); // FP
 public Task DisposeAsync(bool disposing) => fs.Dispose();