Grade commands forces to key in for every student

[nus-pe-bot]

[How to reproduce]

Run grade MATH_Quiz1_10_0.5_3.5

[Expected]

Some students might not have taken the test or subject and an option should be given for teachers to not key in any value

[Actual]

The teacher is forced to key in a value for every student

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_{[original: nus-cs2103-AY2223S1/pe-interim#5596] [original labels: type.FeatureFlaw severity.Medium]}

[jgyj123]

Team's Response

1) Teachers are able to enter the grade of the students based on a specific subject in the command. 2) Teacher can also wait until all students who have taken the test to key in the grade. As our target is primary/secondary school students, the assignments take take are pretty universal (ie. CA1, Mid Years, CA2 and Finals)

Duplicate status (if any):

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