Queue XmppSetAvatarJob when new avatar is uploaded

And let job do nothing in development for now

spec/features/settings/profile_spec.rb

@@ -46,6 +46,8 @@ RSpec.describe 'Profile settings', type: :feature do
 
   feature "Update avatar" do
     scenario "fails with validation error for wrong content type" do
+      expect(LdapManager::UpdateAvatar).not_to receive(:call)
+
       visit setting_path(:profile)
       attach_file "Avatar", "#{Rails.root}/spec/fixtures/files/bitcoin.pdf"
       click_button "Save"
@@ -57,8 +59,7 @@ RSpec.describe 'Profile settings', type: :feature do
     end
 
     scenario "fails with validation error for file size too large" do
-      expect_any_instance_of(LdapManager::UpdateAvatar)
-        .not_to receive(:replace_attribute).and_return(true)
+      expect(LdapManager::UpdateAvatar).not_to receive(:call)
 
       visit setting_path(:profile)
       attach_file "Avatar", "#{Rails.root}/spec/fixtures/files/fsociety-irc.png"
@@ -73,8 +74,12 @@ RSpec.describe 'Profile settings', type: :feature do
     scenario 'works with valid JPG file' do
       file_path = "#{Rails.root}/spec/fixtures/files/taipei.jpg"
 
-      expect_any_instance_of(LdapManager::UpdateAvatar)
-        .to receive(:replace_attribute).and_return(true)
+      expect(LdapManager::UpdateAvatar)
+        .to receive(:call).with(user: user)
+        .and_return(true)
+      expect(XmppSetAvatarJob)
+        .to receive(:perform_later).with(user: user)
+        .and_return(true)
 
       visit setting_path(:profile)
       attach_file "Avatar", file_path
@@ -89,8 +94,12 @@ RSpec.describe 'Profile settings', type: :feature do
     scenario 'works with valid PNG file' do
       file_path = "#{Rails.root}/spec/fixtures/files/bender.png"
 
-      expect_any_instance_of(LdapManager::UpdateAvatar)
-        .to receive(:replace_attribute).and_return(true)
+      expect(LdapManager::UpdateAvatar)
+        .to receive(:call).with(user: user)
+        .and_return(true)
+      expect(XmppSetAvatarJob)
+        .to receive(:perform_later).with(user: user)
+        .and_return(true)
 
       visit setting_path(:profile)
       attach_file "Avatar", file_path