Fiona Gallagher likes to tell a story. It is a story that helps explain how she got to where she is, and one that also encapsulates some of the hard lessons she learned along the way. It is the story of when Gallagher said yes when she really should have said no.    Around ten years ago, Gallagher, then a rising star in Deutsche Bank, was offered an internal promotion that she really did not want to take. The Dublin-born banker simply did not feel the role was the right fit – for her or for her employer. Yet, terrified that…