Add Feature: Edit Student Information

[S-K-Y-Light]

Courses can be edited using the edit Feature.
Previously, User must enter Tags/Courses separately.
Now, User can edit multiple courses in one command, separating courses with ",".

[codecov]

Codecov Report

Attention: Patch coverage is 72.34043% with 13 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
.../seedu/address/logic/parser/EditCommandParser.java	50.00%	9 Missing and 2 partials ⚠️
...java/seedu/address/logic/commands/EditCommand.java	92.00%	0 Missing and 2 partials ⚠️

Files with missing lines	Coverage Δ	Complexity Δ
...java/seedu/address/logic/commands/EditCommand.java	94.11% <92.00%> (ø)	13.00 <2.00> (ø)
.../seedu/address/logic/parser/EditCommandParser.java	67.50% <50.00%> (-25.10%)	12.00 <1.00> (+1.00)	⬇️

[S-K-Y-Light]

TODO: Testing + Write Test Cases

[notnotmax]

lgtm, well done
Acknowledged that you want to write test cases in a separate PR.