**Apache Airflow version**: 2.0.0

**Kubernetes version (if you are using kubernetes)** (use `kubectl version`): n/a

**Environment**: Linux

- **Cloud provider or hardware configuration**: amd64
- **OS** (e.g. from /etc/os-release): Centos 7
- **Kernel** (e.g. `uname -a`):
- **Install tools**: pip
- **Others**:

**What happened**:

The field `sql` is rendered as a serialized json `["select 1 from dual", "select 2 from dual"]` instead of a list of syntax-highlighted SQL statements.

![image](https://user-images.githubusercontent.com/5377410/106365382-2f8a1e80-6370-11eb-981a-43bf71e7b396.png)

**What you expected to happen**:

`lists` and `dicts` should be rendered as lists and dicts rather than serialized json unless the `template_field_renderer` is `json`

![image](https://user-images.githubusercontent.com/5377410/106365216-f3a28980-636e-11eb-9c48-15deb1fbe0d7.png)


**How to reproduce it**:

```
from airflow import DAG
from airflow.providers.oracle.operators.oracle import OracleOperator

with DAG("demo", default_args={owner='airflow'}, start_date= pendulum.yesterday(), schedule_interval='@daily',) as dag:
    OracleOperator(task_id='single', sql='select 1 from dual')
    OracleOperator(task_id='list', sql=['select 1 from dual', 'select 2 from dual'])
```

**Anything else we need to know**:

Introduced by #11061, .

A quick and dirty work-around:

Edit file [airflow/www/views.py](https://github.com/PolideaInternal/airflow/blob/13ba1ec5494848d4a54b3291bd8db5841bfad72e/airflow/www/views.py#L673)

```
            if renderer in renderers:
-                if isinstance(content, (dict, list)):
+               if isinstance(content, (dict, list)) and renderer is renderers['json']:
                    content = json.dumps(content, sort_keys=True, indent=4)
                html_dict[template_field] = renderers[renderer](content)
```
airflow/www/views.py
execution_date,
            confirmed,
            upstream,
            downstream,
            future,
            past,
            State.SUCCESS,
        )
    @expose('/tree')
    @auth.has_access(
        [
            (permissions.ACTION_CAN_READ, permissions.RESOURCE_DAG),
            (permissions.ACTION_CAN_READ, permissions.RESOURCE_TASK_INSTANCE),
            (permissions.ACTION_CAN_READ, permissions.RESOURCE_TASK_LOG),
        ]
    )
    @gzipped  
    @action_logging  
    def tree(self):
        """Get Dag as tree."""
        dag_id = request.args.get('dag_id')
        blur = conf.getboolean('webserver', 'demo_mode')
        dag = current_app.dag_bag.get_dag(dag_id)
        if not dag:
            flash(f'DAG "{dag_id}" seems to be missing from DagBag.', "error")
            return redirect(url_for('Airflow.index'))
        root = request.args.get('root')
        if root:
            dag = dag.sub_dag(task_ids_or_regex=root, include_downstream=False, include_upstream=True)
        base_date = request.args.get('base_date')