Remove multiple calls to SetActiveAttribute
For the Lagrange and Bezier cells, SetActiveAttribute was called to check if the rational weights or the cell degrees attributes were defined or not, whereas this could have been done by checking directly the validity of the pointer returned by the function GetHigherOrderDegrees or GetRationalWeights.
Some SetActiveAttribute calls have been already removed in this MR !7411 (merged) since they were found to be not thread safe. Removing the remaining ones.
@tjcorona please review and run the tests.