JsonAdaptedPerson: Change variable name tagged -> tags

The JsonAdaptedPerson class contains a list object called 'tagged'.

According to our coding standard, a variable holding a collection
of items should have a plural form name.

Let's change the variable name to 'tags' instead.

src/main/java/seedu/address/storage/JsonAdaptedPerson.java

@@ -28,21 +28,21 @@ class JsonAdaptedPerson {
     private final String phone;
     private final String email;
     private final String address;
-    private final List<JsonAdaptedTag> tagged = new ArrayList<>();
+    private final List<JsonAdaptedTag> tags = new ArrayList<>();
 
     /**
      * Constructs a {@code JsonAdaptedPerson} with the given person details.
      */
     @JsonCreator
     public JsonAdaptedPerson(@JsonProperty("name") String name, @JsonProperty("phone") String phone,
             @JsonProperty("email") String email, @JsonProperty("address") String address,
-            @JsonProperty("tagged") List<JsonAdaptedTag> tagged) {
+            @JsonProperty("tagged") List<JsonAdaptedTag> tags) {
         this.name = name;
         this.phone = phone;
         this.email = email;
         this.address = address;
-        if (tagged != null) {
-            this.tagged.addAll(tagged);
+        if (tags != null) {
+            this.tags.addAll(tags);
         }
     }
 
@@ -54,7 +54,7 @@ public JsonAdaptedPerson(Person source) {
         phone = source.getPhone().value;
         email = source.getEmail().value;
         address = source.getAddress().value;
-        tagged.addAll(source.getTags().stream()
+        tags.addAll(source.getTags().stream()
                 .map(JsonAdaptedTag::new)
                 .collect(Collectors.toList()));
     }
@@ -66,7 +66,7 @@ public JsonAdaptedPerson(Person source) {
      */
     public Person toModelType() throws IllegalValueException {
         final List<Tag> personTags = new ArrayList<>();
-        for (JsonAdaptedTag tag : tagged) {
+        for (JsonAdaptedTag tag : tags) {
             personTags.add(tag.toModelType());
         }