### Apache Airflow version

2.4.1

### What happened

When there are large number of dag files, lets say 10K and each takes sometime to parse,  dag_parser doesnt pick any newly created files till all 10k files are finished parsing

`if not self._file_path_queue:
                self.emit_metrics()
                self.prepare_file_path_queue()`

Above logic only adds new files to queue when queue is empty

### What you think should happen instead

Every loop of dag processor should pick new files and add into file for parsing queue

### How to reproduce

_No response_

### Operating System

All

### Versions of Apache Airflow Providers

_No response_

### Deployment

Docker-Compose

### Deployment details

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

"""
        Detects DAGs which are no longer present in files
        Deactivate them and remove them in the serialized_dag table
        """
        now = timezone.utcnow()
        elapsed_time_since_refresh = (now - self.last_deactivate_stale_dags_time).total_seconds()
        if elapsed_time_since_refresh > self.deactivate_stale_dags_interval:
            last_parsed = {
                fp: self.get_last_finish_time(fp) for fp in self.file_paths if self.get_last_finish_time(fp)
            }
            to_deactivate = set()
            query = session.query(DagModel.dag_id, DagModel.fileloc, DagModel.last_parsed_time).filter(
                DagModel.is_active
            )
            if self.standalone_dag_processor:
                query = query.filter(DagModel.processor_subdir == self.get_dag_directory())
            dags_parsed = query.all()
            for dag in dags_parsed:
                
                
                
                if (
                    dag.fileloc in last_parsed
                    and (dag.last_parsed_time + self._processor_timeout) < last_parsed[dag.fileloc]