Sketcher: Solver information: Bug fix

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When the solver converged (but did not succeed) or when the solver succeded but the solution is not OCC-valid, no error message was shown in the solver messages dialog.

src/Mod/Sketcher/App/Sketch.cpp

@@ -2186,6 +2186,7 @@ int Sketch::solve(void)
                     GCSsys.undoSolution();
                     updateGeometry();
                     Base::Console().Warning("Invalid solution from %s solver.\n", solvername.c_str());
+                    ret = GCS::SuccessfulSolutionInvalid;
                 }else
                 {
                     updateNonDrivingConstraints();