Fix various typos

Missed by the codespell CI not being functional for a period of time.

src/Mod/Fem/App/AppFemPy.cpp

@@ -350,7 +350,7 @@ private:
             throw Py::Exception();
         }
 
-        // if non is returned the VTK object was created by annother VTK library, and the
+        // if none is returned the VTK object was created by another VTK library, and the
         // python api used to create it cannot be used with FreeCAD
         vtkObjectBase* obj = vtkPythonUtil::GetPointerFromObject(pcObj, "vtkObject");
         if (!obj) {

src/Mod/Fem/App/FemPostFilter.cpp

@@ -88,7 +88,7 @@ FemPostFilter::FilterPipeline& FemPostFilter::getFilterPipeline(std::string name
 void FemPostFilter::setActiveFilterPipeline(std::string name)
 {
     if (m_pipelines.count(name) == 0) {
-        throw Base::ValueError("Not a filter pipline name");
+        throw Base::ValueError("Not a filter pipeline name");
     }
 
     if (m_activePipeline != name && isValid()) {