**Apache Airflow version**:

2.1.0

**Environment**:

- self hosted docker-compose based stack

**What happened**:

Using JDBCOperator if the sql result in an error we got only 
```
[2021-06-21 11:05:55,377] {local_task_job.py:151} INFO - Task exited with return code 1
```

Before upgrading from 2.0.1 we got error details in logs:
```
jaydebeapi.DatabaseError: java.sql.SQLException:... [MapR][DrillJDBCDriver](500165) Query execution error. Details: VALIDATION ERROR:...
``` 

**What you expected to happen**:

See `SQLException` in logs

**How to reproduce it**:

Perform a generic SQL task with broken SQL.

**Anything else we need to know**:

I think is somehow related to https://github.com/apache/airflow/commit/abcd48731303d9e141bdc94acc2db46d73ccbe12#diff-4fd3febb74d94b2953bf5e9b4a981b617949195f83d96f4a589c3078085959b7R202 
airflow/models/taskinstance.py
if dag_run and dag_run.external_trigger:
            prev_execution_date = self.execution_date
            next_execution_date = self.execution_date
        else:
            prev_execution_date = task.dag.previous_schedule(self.execution_date)
            next_execution_date = task.dag.following_schedule(self.execution_date)
        next_ds = None
        next_ds_nodash = None
        if next_execution_date:
            next_ds = next_execution_date.strftime('%Y-%m-%d')
            next_ds_nodash = next_ds.replace('-', '')
            next_execution_date = pendulum.instance(next_execution_date)
        prev_ds = None
        prev_ds_nodash = None
        if prev_execution_date:
            prev_ds = prev_execution_date.strftime('%Y-%m-%d')
            prev_ds_nodash = prev_ds.replace('-', '')
            prev_execution_date = pendulum.instance(prev_execution_date)
        ds_nodash = ds.replace('-', '')
        ts_nodash = self.execution_date.strftime('%Y%m%dT%H%M%S')
        ts_nodash_with_tz = ts.replace('-', '').replace(':', '')
        yesterday_ds_nodash = yesterday_ds.replace('-', '')
        tomorrow_ds_nodash = tomorrow_ds.replace('-', '')
        ti_key_str = f"{task.dag_id}__{task.task_id}__{ds_nodash}"
        if task.params:
            params.update(task.params)
        if conf.getboolean('core', 'dag_run_conf_overrides_params'):
            self.overwrite_params_with_dag_run_conf(params=params, dag_run=dag_run)
        class VariableAccessor: