Part: Improve TopoShape::findPlane

Since OCC 7.7 using GeomLib_IsPlanarSurface without a custom tolerance may fail because the default value is too strict.
To fix this problem forward the passed tolerance value to GeomLib_IsPlanarSurface.

This fixes issue 20633

src/Mod/Part/App/TopoShape.cpp

@@ -3970,7 +3970,7 @@ bool TopoShape::findPlane(gp_Pln& pln, double tol, double atol) const
             else {
                 TopLoc_Location loc;
                 Handle(Geom_Surface) surf = BRep_Tool::Surface(face, loc);
-                GeomLib_IsPlanarSurface check(surf);
+                GeomLib_IsPlanarSurface check(surf, tol);
                 if (check.IsPlanar()) {
                     plane = check.Plan();
                 }