Don't load unnecessary histograms
HITowerWeightTool used to load some histograms even if it was unnecessary, as the switch (m_applycorrection) for application this weight was set to false. Now, we only load these histograms if such switch is true.
Moreover, if the usage of the weight was disabled, HIEventShapeFillerTool was still creating the HITowerWeightTool although it was never used. It created the HITowerWeightTool with the default setup, i.e. when m_applycorrection is true.
Related ticket: ATLHI-489