Update DuplicatePhoneTagger and Related Files

[valhrd]

DuplicatePhoneTagger is now used in the following classes:

• Logic classes
  • AddCommand.java
  • DeleteCommand.java
  • EditCommand.java
• Non-logic classes
  • MainApp.java (To read the JSON in the event it contains duplicate phone numbers and it is the first time the AB sees it)
  • PersonCard.java (To give the tag an FXML ID for CSS purposes)

Used to be in:

• Logic classes
  • EditCommand.java
• Non-logic classes
  • ModelManager.java (Takes advantage of existing ModelManager#addPerson and ModelManager#removePerson methods at the cost of higher coupling)
  • MainApp.java (To read the JSON in the event it contains duplicate phone numbers and it is the first time the AB sees it)
  • PersonCard.java (To give the tag an FXML ID for CSS purposes)

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Files with missing lines	Coverage Δ	Complexity Δ
.../java/seedu/address/logic/commands/AddCommand.java	100.00% <100.00%> (ø)	8.00 <0.00> (ø)
...va/seedu/address/logic/commands/DeleteCommand.java	100.00% <100.00%> (ø)	8.00 <1.00> (+1.00)
...du/address/logic/handler/DuplicatePhoneTagger.java	93.33% <100.00%> (+0.47%)	16.00 <0.00> (ø)
...rc/main/java/seedu/address/model/ModelManager.java	100.00% <ø> (ø)	23.00 <0.00> (ø)