**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
"""Show Circles on screen for any error in the Webserver"""
    return (
        render_template(
            'airflow/circles.html',
            hostname=socket.getfqdn()
            if conf.getboolean('webserver', 'EXPOSE_HOSTNAME', fallback=True)  
            else 'redact',
        ),
        404,
    )
def show_traceback(error):  
    """Show Traceback for a given error"""
    return (
        render_template(
            'airflow/traceback.html',  
            python_version=sys.version.split(" ")[0],
            airflow_version=version,
            hostname=socket.getfqdn()
            if conf.getboolean('webserver', 'EXPOSE_HOSTNAME', fallback=True)
            else 'redact',
            info=traceback.format_exc()
            if conf.getboolean('webserver', 'EXPOSE_STACKTRACE', fallback=True)
            else 'Error! Please contact server admin.',
        ),
        500,
    )
class AirflowBaseView(BaseView):