refactor: remove git validation from initializer and add setter method in Person class

lab2/person.rb

@@ -5,7 +5,6 @@ class Person
 
   def initialize(id:, git:, contact: Contact.new)
     validate_id(id)
-    validate_git(git)
     validate_contact(contact)
 
     @id = id
@@ -33,6 +32,11 @@ class Person
     id.is_a?(String) && !id.strip.empty?
   end
 
+  def git=(git)
+    validate_git(git)
+    @git = git
+  end
+
   private
 
   def validate_id(id)