Add schedule tests

[dhafinrazaq]

No description provided.

[codecov]

Codecov Report

Merging #158 into master will increase coverage by 0.29%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #158      +/-   ##
============================================
+ Coverage     68.43%   68.72%   +0.29%     
- Complexity      713      719       +6     
============================================
  Files           106      106              
  Lines          2411     2411              
  Branches        284      284              
============================================
+ Hits           1650     1657       +7     
+ Misses          654      651       -3     
+ Partials        107      103       -4     

Impacted Files	Coverage Δ	Complexity Δ
...va/seedu/address/model/schedule/PaymentStatus.java	60.00% <0.00%> (+6.66%)	11.00% <0.00%> (+1.00%)
...in/java/seedu/address/model/schedule/Schedule.java	91.66% <0.00%> (+16.66%)	20.00% <0.00%> (+5.00%)

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