Corrected grade should always be taken into account

[goomens]

After a grade has been corrected, it should be used instead of the original grade to determine

• [x] The color of the cell border (insufficient/sufficient)
• [x] Whether a retake grade box is shown by default and required (i.e. if the original grade was insufficient, but the correction is sufficient, the retake should be optional as if the original grade were sufficient)