Gui: Use getObject<T>() helpers in classes

This commit is generated using regex based find and replace:

```
s/[\w:]+_cast\s*<([^>]+)\*>\s*\(\s*getObject\(\s*\)\)/getObject<$1>/
s/[\w:]+_cast\s*<([^>]+)\*>\s*\(\s*([^)]*)\s*->\s*getObject\(\s*\)\)/$2->getObject<$1>()/
```

To regenerate if needed.

src/Mod/PartDesign/Gui/ViewProviderExtrude.cpp

@@ -42,7 +42,7 @@ PROPERTY_SOURCE(PartDesignGui::ViewProviderExtrude, PartDesignGui::ViewProviderS
 
 void PartDesignGui::ViewProviderExtrude::highlightShapeFaces(const std::vector<std::string>& faces)
 {
-    auto extrude = static_cast<PartDesign::FeatureExtrude*>(getObject());
+    auto extrude = getObject<PartDesign::FeatureExtrude>();
     auto base = static_cast<Part::Feature*>(extrude->UpToShape.getValue());
 
     auto baseViewProvider =