**What happened:**

My password for external Postgres RDS contained '@123' at the end which got appended to the host of the DB due to some bug. One can notice in the logs, the DB_HOST has an unwanted 123@ in the front of it  DB_HOST=**123@**{{postgres_host}}. I removed '@' character from the password and it worked fine. 

I am using the latest image of apache/airflow and using the official helm chart.

```
kc logs airflow-run-airflow-migrations-xxx
BACKEND=postgresql
DB_HOST=123@{{postgres_host}}
DB_PORT=5432
....................
ERROR! Maximum number of retries (20) reached.

Last check result:
$ run_nc '123@{{postgres_host}}' '5432'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
socket.gaierror: [Errno -2] Name or service not known
Can't parse  as an IP address
```

**Steps to reproduce:**
One can easily reproduce this by using a password that contains the '@' character in it.
```
data:
  metadataConnection:
    user: {{postgres_airflow_username}}
    pass: {{postgres_airflow_password}}
    protocol: postgresql  
    host: {{postgres_host}}
    port: 5432
    db: {{postgres_airflow_dbname}}
```

**Expected behavior:**
Migrations should run irrespective if the Postgres password contains an @ character or not.
chart/tests/test_redis.py
]
                            }
                        }
                    },
                    "tolerations": [
                        {"key": "dynamic-pods", "operator": "Equal", "value": "true", "effect": "NoSchedule"}
                    ],
                    "nodeSelector": {"diskType": "ssd"},
                },
            },
            show_only=["templates/redis/redis-statefulset.yaml"],
        )
        assert "StatefulSet" == jmespath.search("kind", docs[0])
        assert "foo" == jmespath.search(
            "spec.template.spec.affinity.nodeAffinity."
            "requiredDuringSchedulingIgnoredDuringExecution."
            "nodeSelectorTerms[0]."
            "matchExpressions[0]."
            "key",
            docs[0],
        )
        assert "ssd" == jmespath.search(
            "spec.template.spec.nodeSelector.diskType",
            docs[0],
        )
        assert "dynamic-pods" == jmespath.search(
            "spec.template.spec.tolerations[0].key",
            docs[0],
        )
    def test_redis_resources_are_configurable(self):