Properly stub MailBluster calls in FactoryBot user creation

spec/factories/users.rb

@@ -80,15 +80,16 @@ FactoryBot.define do
     last_sign_in_at { Date.today }
     is_disabled { false }
 
+    after(:build) do |user|
       url_mailbluster = 'https://api.mailbluster.com/api/leads/'
       response_body = "{
         \"message\": \"Lead created\",
         \"lead\": {
           \"id\": 329395,
-        \"firstName\": \"#{name}\",
+          \"firstName\": \"#{user.name}\",
           \"lastName\": \"\",
-        \"fullName\": \"#{name}\",
+          \"fullName\": \"#{user.name}\",
-        \"email\": \"#{email}\",
+          \"email\": \"#{user.email}\",
           \"subscribed\": true,
           \"tags\": [
             #{ENV['OSEM_NAME'] || 'snapcon'}
@@ -96,6 +97,7 @@ FactoryBot.define do
         }
       }"
       WebMock.stub_request(:post, url_mailbluster)
+    end
     # Called by every user creation
 
     after(:create) do |user|

spec/models/user_spec.rb

@@ -533,7 +533,8 @@ describe User do
 
   describe 'mailbluster' do
     it 'creates a Mailbluster lead on creating a user' do
-      user_mailbluster = User.new(name: 'John Doe', email: 'snap@qwertyuiop.org')
+      user_mailbluster = build(:user)
+      url = 'https://api.mailbluster.com/api/leads/'
 
       response_body = "{
         \"message\": \"Lead created\",
@@ -549,7 +550,7 @@ describe User do
           ],
         }
       }"
-      stub_request(:post, url_mailbluster)
+      stub_request(:post, url)
         .to_return(body: response_body, status: 200)
 
       # Do not request before save