Modify specs tests because model validations changed

spec/models/category_spec.rb

@@ -4,7 +4,7 @@
   let(:user) { User.create(name: 'John Doe', email: 'foo@bar.com', password: '123456') }
 
   it 'is valid with a name and user' do
-    category = Category.new(name: 'Food', user:)
+    category = Category.new(name: 'Food', icon: '🍴', user:)
     expect(category).to be_valid
   end
 
@@ -15,8 +15,8 @@
 
   it 'allows the same category name for different users' do
     another_user = User.create(name: 'Alice', email: 'alice@bar.com', password: '654321')
-    Category.create(name: 'Food', user:)
-    category2 = Category.new(name: 'Food', user: another_user)
+    Category.create(name: 'Food', icon: '🍴', user:)
+    category2 = Category.new(name: 'Food', icon: '🍴', user: another_user)
     expect(category2).to be_valid
   end
 end

spec/models/expense_spec.rb

@@ -2,7 +2,7 @@
 
 RSpec.describe Expense, type: :model do
   let(:user) { User.create(name: 'John Doe', email: 'foo@bar.com', password: '123456') }
-  let(:category) { Category.create(name: 'Food', user:) }
+  let(:category) { Category.create(name: 'Food', icon: '🍴', user:) }
 
   it 'is associated with a category' do
     expense = Expense.new(amount: 25, category:)
@@ -25,7 +25,7 @@
   end
 
   it 'can save a valid expense' do
-    expense = Expense.new(amount: 50, category:, author: user)
+    expense = Expense.new(name: 'Pizza', amount: 25, category:, author: user)
     expect(expense).to be_valid
   end
 end