FIX: Ensure revoke_ungranted_titles! works with user_ids (#31371)

When `revoke_ungranted_titles!` was invoked, the optional list of
`user_ids` was not passed from the argument list to the query. This
resulted in an exception because the placeholder `:user_ids` existed in
the query.

app/services/badge_granter.rb

@@ -504,9 +504,7 @@ class BadgeGranter
   end
 
   def self.revoke_ungranted_titles!(user_ids = nil)
-    user_ids = user_ids.join(", ") if user_ids
-
-    DB.exec <<~SQL
+    DB.exec <<~SQL, user_ids: user_ids
       UPDATE users u
       SET title = ''
       FROM user_profiles up
@@ -525,7 +523,7 @@ class BadgeGranter
         #{user_ids.present? ? "AND u.id IN (:user_ids)" : ""}
     SQL
 
-    DB.exec <<~SQL
+    DB.exec <<~SQL, user_ids: user_ids
       UPDATE user_profiles up
       SET granted_title_badge_id = NULL
       FROM users u

spec/services/badge_granter_spec.rb

@@ -11,10 +11,24 @@ RSpec.describe BadgeGranter do
     BadgeGranter.clear_queue!
   end
 
-  describe "revoke_titles" do
+  describe ".revoke_ungranted_titles!" do
     let(:user) { Fabricate(:user) }
+    let(:other_user) { Fabricate(:user) }
     let(:badge) { Fabricate(:badge, allow_title: true) }
 
+    it "can revoke title of a single user" do
+      BadgeGranter.grant(badge, user)
+      user.update!(title: badge.name)
+      BadgeGranter.grant(badge, other_user)
+      other_user.update!(title: badge.name)
+
+      badge.update_column(:enabled, false)
+      BadgeGranter.revoke_ungranted_titles!([user.id])
+
+      expect(user.reload.title).to be_blank
+      expect(other_user.reload.title).to eq(badge.name)
+    end
+
     it "revokes title when badge is not allowed as title" do
       BadgeGranter.grant(badge, user)
       user.update!(title: badge.name)