Fix linter errors

Gemfile

@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 
 gem 'rubocop', '>= 1.0', '< 2.0'
 
 gem 'json'
 
-gem "rspec"
+gem 'rspec'

spec/classroom_spec.rb

@@ -11,8 +11,8 @@
   end
 
   it 'can add students' do
-    student1 = Student.new(classroom, 18, 'Alice') # Provide age and name
-    student2 = Student.new(classroom, 19, 'Bob')   # Provide age and name
+    student1 = Student.new(classroom, 18, 'Alice')
+    student2 = Student.new(classroom, 19, 'Bob')   
 
     classroom.add_student(student1)
     classroom.add_student(student2)

spec/person_spec.rb

@@ -1,7 +1,7 @@
 require './person'
 
 describe Person.new 23, 'Abdu' do
-    it{is_expected.to have_attributes(age: 23) } 
-    it{is_expected.to have_attributes(name: 'Abdu') } 
-    it{is_expected.to have_attributes(parent_permission: true) } 
-    end
+  it { is_expected.to have_attributes(age: 23) }
+  it { is_expected.to have_attributes(name: 'Abdu') }
+  it { is_expected.to have_attributes(parent_permission: true) }
+end

spec/rental_spec.rb

@@ -17,4 +17,4 @@
     expect(book.rentals).to contain_exactly(rental)
     expect(person.rentals).to contain_exactly(rental)
   end
-end
+end

spec/student_spec.rb

@@ -1,9 +1,9 @@
 require './student'
 
 describe Student.new 'IT', 24, 'Abdu' do
-    it { is_expected.to be_a(Person) } 
-    it{is_expected.to have_attributes(classroom: 'IT') } 
-    it{is_expected.to have_attributes(age: 24) } 
-    it{is_expected.to have_attributes(name: 'Abdu') } 
-    it{is_expected.to have_attributes(parent_permission: true) } 
-    end
+  it { is_expected.to be_a(Person) }
+  it { is_expected.to have_attributes(classroom: 'IT') }
+  it { is_expected.to have_attributes(age: 24) }
+  it { is_expected.to have_attributes(name: 'Abdu') }
+  it { is_expected.to have_attributes(parent_permission: true) }
+end

spec/teacher_spec.rb

@@ -3,9 +3,9 @@
 describe Teacher do
   subject(:teacher) { described_class.new('Math', 35, 'John Doe') }
 
-  it { is_expected.to be_a(Person) } # Ensure Teacher is a subclass of Person
+  it { is_expected.to be_a(Person) } 
   it { is_expected.to have_attributes(specialization: 'Math', age: 35, name: 'John Doe') }
-  
+
   it 'can use services' do
     expect(teacher.can_use_services?).to be(true)
   end