adapt to changes in ranges in 3.4.1

app/models/users/scopes/having_reminder_mail_to_send.rb

@@ -183,8 +183,13 @@ def quarters_between_earliest_and_latest(earliest_time, latest_time) # rubocop:d
         # The last quarter is the one smaller than the latest time. But needs to be at least equal to the first quarter.
         last_quarter = [first_quarter, latest_time.change(min: latest_time.min / 15 * 15)].max
 
-        (first_quarter.to_i..last_quarter.to_i)
-          .step(15.minutes)
+        quarters = if first_quarter == last_quarter
+                     [first_quarter]
+                   else
+                     (first_quarter.to_i..last_quarter.to_i).step(15.minutes)
+                   end
+
+        quarters
           .map do |time|
           Time.zone.at(time)
         end

app/workers/notifications/schedule_date_alerts_notifications_job.rb

@@ -35,7 +35,7 @@ class ScheduleDateAlertsNotificationsJob < ApplicationJob
     def perform
       return unless EnterpriseToken.allows_to?(:date_alerts)
 
-      Service.new(every_quater_hour_between_predecessor_cron_at_and_own_cron_at).call
+      Service.new(every_quarter_hour_between_predecessor_cron_at_and_own_cron_at).call
     end
 
     # What cannot be controlled is the time at which a job is actually performed.
@@ -70,9 +70,14 @@ def perform
     # for 1:00 am local time are covered. The sole exception would be the case where previously finished jobs
     # have been removed from the database and the current job took longer to start executing. This is for now
     # an accepted shortcoming as the likelihood of this happening is considered to be very low.
-    def every_quater_hour_between_predecessor_cron_at_and_own_cron_at
-      (lower_boundary.to_i..upper_boundary.to_i)
-        .step(15.minutes)
+    def every_quarter_hour_between_predecessor_cron_at_and_own_cron_at
+      quarters = (lower_boundary.to_i..upper_boundary.to_i).step(15.minutes).to_a
+
+      if quarters.empty? && lower_boundary.present?
+        quarters = [lower_boundary]
+      end
+
+      quarters
         .map do |time|
         Time.zone.at(time)
       end

spec/models/users/scopes/having_reminder_mail_to_send_spec.rb

@@ -380,7 +380,7 @@
       )
     end
     let(:scope_upper_boundary_time) { ActiveSupport::TimeZone["Europe/Paris"].parse("2021-09-30T08:09").utc }
-    let(:scope_lower_boundary_time) { ActiveSupport::TimeZone["Europe/Paris"].parse("2021-09-30T08:00") }
+    let(:scope_lower_boundary_time) { ActiveSupport::TimeZone["Europe/Paris"].parse("2021-09-30T08:00").utc }
 
     it "contains the user" do
       expect(scope)
@@ -399,7 +399,7 @@
       )
     end
     let(:scope_upper_boundary_time) { ActiveSupport::TimeZone["Europe/Paris"].parse("2021-09-30T10:00").utc }
-    let(:scope_lower_boundary_time) { ActiveSupport::TimeZone["Europe/Paris"].parse("2021-09-30T10:00") }
+    let(:scope_lower_boundary_time) { ActiveSupport::TimeZone["Europe/Paris"].parse("2021-09-30T10:00").utc }
 
     it "is empty" do
       expect(scope)