Most recent Asset events ignored when max_active_runs = 1

### Apache Airflow version 3.0.6 ### If "Other Airflow 2 version" selected, which one? _No response_ ### What happened? For a DAG which allows for only one Dag run at a time (`max_active_runs=1`), if multiple events are posted created during processing of the current DagRun, only oldest one is processed while other are ignored. Detailed scenario: 1. Create asset event 1 (timestamp: T1) 2. DAG Run 1 triggers for asset event 1 (run_after = T1) 3. While DAG Run 1 is running: Create asset events 2, 3, and 4 (timestamps: T2, T3, T4) 4. DAG Run 1 completes (consumes only event 1) 5. DAG Run 2 triggers for asset event 2 (run_after = T2) consuming only event 2 6. DAG Run 2 completes 12. No further DAG runs are triggered automatically by the scgheduler 13. Events 3 and 4 are lost forever unless a new asset event (event 5) is created 14. If event 5 is created (timestamp: T5) DAG Run 3 is triggered consuming events 3, 4 and 5 16. Result: Events 3, 4, and 5 are all processed together in DAG Run 3 Timeline: ``` T1=10:00 T2=10:01 T3=10:02 T4=10:03 T5=10:10 │ │ │ │ │ Event1 Event2 Event3 Event4 Event5 │ │ │ │ │ │ │ └─────────┴─────────────► │ │ │ (skipped by DAG Run 2) │ │ │ │ └─►DR1 └─►DR2 └─►DR3 (E1) (E2 only) (E3,E4,E5) ``` Made some SQL queries to confirm that `run_after` for DagRun 2 matches timestamp of event 2 (instead of lastest event 4) ```SQL SELECT start_date, run_after, run_id FROM dag_run WHERE dag_id = '<my_dag_name>' ORDER BY run_after DESC LIMIT 3; "2025-09-24 11:54:00.343726+00" "2025-09-24 11:53:59.679149+00" "asset_triggered__2025-09-24T11:53:59.679149+00:00_mnhsp7QE" # DagRun 3 "2025-09-24 11:48:34.438651+00" "2025-09-24 11:45:29.587827+00" "asset_triggered__2025-09-24T11:45:29.587827+00:00_Pw3gZ43A" # DagRun 2 (run_after…