### 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)

self.set_file_paths(self._file_paths)
            try:
                self.log.debug("Removing old import errors")
                self.clear_nonexistent_import_errors()
            except Exception:
                self.log.exception("Error removing old import errors")
            
            
            
            dag_filelocs = []
            for fileloc in self._file_paths:
                if not fileloc.endswith(".py") and zipfile.is_zipfile(fileloc):
                    with zipfile.ZipFile(fileloc) as z:
                        dag_filelocs.extend(
                            [
                                os.path.join(fileloc, info.filename)
                                for info in z.infolist()
                                if might_contain_dag(info.filename, True, z)
                            ]
                        )
                else:
                    dag_filelocs.append(fileloc)
            SerializedDagModel.remove_deleted_dags(
                alive_dag_filelocs=dag_filelocs,
                processor_subdir=self.get_dag_directory(),
            )
            DagModel.deactivate_deleted_dags(self._file_paths)
            from airflow.models.dagcode import DagCode
            DagCode.remove_deleted_code(dag_filelocs)
    def _print_stat(self):