### Apache Airflow version

2.3.3 (latest released)

### What happened

An URL I saved in the past, `https://astronomer.astronomer.run/dx4o2568/home?tags=test`,  has the tag field in the query parameter though I was not aware of this. When I clicked on the URL, I was confused because I did not see any DAGs when I should have a bunch.

After closer inspection, I realized that the URL has the tag field in the query parameter but then noticed that the tag box in the Airflow UI wasn't properly populated.

![screen_shot_2022-07-12_at_8 11 07_am](https://user-images.githubusercontent.com/5952735/182496710-601b4a98-aacb-4482-bb9f-bb3fdf9e265f.png)


### What you think should happen instead

When I clicked on the URL, the tag box should have been populated with the strings in the URL.

### How to reproduce

Start an Airflow deployment with some DAGs and add the tag query parameter. More specifically, it has to be a tag that is not used by any DAG.

### Operating System

N/A

### Versions of Apache Airflow Providers

_No response_

### Deployment

Astronomer

### 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)

"""Show GANTT chart."""
        dag = get_airflow_app().dag_bag.get_dag(dag_id, session=session)
        dag_model = DagModel.get_dagmodel(dag_id, session=session)
        if not dag:
            flash(f'DAG "{dag_id}" seems to be missing.', "error")
            return redirect(url_for("Airflow.index"))
        wwwutils.check_import_errors(dag.fileloc, session)
        wwwutils.check_dag_warnings(dag.dag_id, session)
        root = request.args.get("root")
        if root:
            dag = dag.partial_subset(task_ids_or_regex=root, include_upstream=True, include_downstream=False)
        dt_nr_dr_data = get_date_time_num_runs_dag_runs_form_data(request, session, dag)
        dttm = dt_nr_dr_data["dttm"]
        dag_run = dag.get_dagrun(execution_date=dttm)
        dag_run_id = dag_run.run_id if dag_run else None
        form = DateTimeWithNumRunsWithDagRunsForm(data=dt_nr_dr_data)
        form.execution_date.choices = dt_nr_dr_data["dr_choices"]
        tis = (
            session.query(TaskInstance)
            .filter(
                TaskInstance.dag_id == dag_id,
                TaskInstance.run_id == dag_run_id,
                TaskInstance.start_date.isnot(None),
                TaskInstance.state.isnot(None),
            )
            .order_by(TaskInstance.start_date)
        )
        ti_fails = session.query(TaskFail).filter_by(run_id=dag_run_id, dag_id=dag_id)
        if dag.partial: