Remove unused User.internal scope

It looks like it's not used anymore

app/models/user.rb

@@ -324,6 +324,7 @@ class User < ApplicationRecord
   scope :active, -> { with_state(:active).non_internal }
   scope :active_without_ghosts, -> { with_state(:active).without_ghosts }
   scope :without_ghosts, -> { humans.or(where.not(user_type: :ghost)) }
+  scope :non_internal, -> { without_ghosts.with_project_bots }
   scope :deactivated, -> { with_state(:deactivated).non_internal }
   scope :without_projects, -> { joins('LEFT JOIN project_authorizations ON users.id = project_authorizations.user_id').where(project_authorizations: { user_id: nil }) }
   scope :order_recent_sign_in, -> { reorder(Gitlab::Database.nulls_last_order('current_sign_in_at', 'DESC')) }
@@ -650,6 +651,10 @@ class User < ApplicationRecord
     end
   end
 
+  #
+  # Instance methods
+  #
+
   def full_path
     username
   end
@@ -664,24 +669,6 @@ class User < ApplicationRecord
     ghost? || (bot? && !project_bot?)
   end
   
-  def self.internal
-    where(user_type: :ghost).or(bots)
-  end
-
-  # The explicit check for project_bot will be removed with Bot Categorization
-  # Ref: https://gitlab.com/gitlab-org/gitlab/-/issues/213945
-  def self.non_internal
-    without_ghosts.with_project_bots
-  end
-
-  def human?
-    user_type.nil?
-  end
-
-  #
-  # Instance methods
-  #
-
   def to_param
     username
   end

spec/models/user_spec.rb

@@ -4354,31 +4354,31 @@ describe User, :do_not_mock_admin_mode do
     end
   end
 
-  describe 'internal methods' do
-    let_it_be(:user) { create(:user) }
-    let_it_be(:ghost) { described_class.ghost }
-    let_it_be(:alert_bot) { described_class.alert_bot }
-    let_it_be(:project_bot) { create(:user, :project_bot) }
-    let_it_be(:non_internal) { [user, project_bot] }
-    let_it_be(:internal) { [ghost, alert_bot] }
-
-    it 'returns internal users' do
-      expect(described_class.internal).to match_array(internal)
-      expect(internal.all?(&:internal?)).to eq(true)
-    end
+  describe '.non_internal' do
+    let!(:user) { create(:user) }
+    let!(:ghost) { described_class.ghost }
+    let!(:alert_bot) { described_class.alert_bot }
+    let!(:project_bot) { create(:user, :project_bot) }
+    let(:non_internal) { [user, project_bot] }
 
     it 'returns non internal users' do
-      expect(described_class.non_internal).to match_array(non_internal)
+      expect(described_class.non_internal).to eq(non_internal)
       expect(non_internal.all?(&:internal?)).to eq(false)
     end
+  end
 
   describe '#bot?' do
+    let!(:user) { create(:user) }
+    let!(:ghost) { described_class.ghost }
+    let!(:alert_bot) { described_class.alert_bot }
+    let!(:project_bot) { create(:user, :project_bot) }
+
     it 'marks bot users' do
-        expect(user.bot?).to eq(false)
-        expect(ghost.bot?).to eq(false)
+      expect(user).not_to be_bot
+      expect(ghost).not_to be_bot
 
-        expect(alert_bot.bot?).to eq(true)
-      end
+      expect(alert_bot).to be_bot
+      expect(project_bot).to be_bot
     end
   end