### Official Helm Chart version

1.2.0

### Apache Airflow version

2.1.4

### Kubernetes Version

v1.21.6+bb8d50a

### Helm Chart configuration

I defined a new Connection String for AIRFLOW_CONN_SPARK_DEFAULT in values.yaml like the following section (base64 encoded or with correct string (spark://k8s://100.68.0.1:443?deploy-mode=cluster):

```
extraSecrets:
  '{{ .Release.Name }}-airflow-connections':
     data: |
       AIRFLOW_CONN_SPARK_DEFAULT: 'c3Bhcms6Ly9rOHM6Ly8xMDAuNjguMC4xOjQ0Mz9kZXBsb3ktbW9kZT1jbHVzdGVy'
```

in Section extraEnvFrom i defined the following:

```
extraEnvFrom: |
   - secretRef:
       name: '{{ .Release.Name }}-airflow-connections'
```

### Docker Image customisations

added apache-airflow-providers-apache-spark to base Image

### What happened

Airflow Connection mapped wrong because of the k8s:// within the url.  if i ask for the connection with cmd "airflow connections get spark_default" then host=k8s and schema=/100.60.0.1:443 which is wrong

### What you expected to happen

the spark Connection based on k8s (spark://k8s://100.68.0.1:443?deploy-mode=cluster) should be parsed correctly

### How to reproduce

define in values.yaml

```
extraSecrets:
  '{{ .Release.Name }}-airflow-connections':
     data: |
       AIRFLOW_CONN_SPARK_DEFAULT: 'c3Bhcms6Ly9rOHM6Ly8xMDAuNjguMC4xOjQ0Mz9kZXBsb3ktbW9kZT1jbHVzdGVy'

extraEnvFrom: |
   - secretRef:
       name: '{{ .Release.Name }}-airflow-connections'
```


### Anything else

_No response_

### Are you willing to submit PR?

- [ ] 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)

"""Password. The value is decrypted/encrypted when reading/setting the value."""
        return synonym("_password", descriptor=property(cls.get_password, cls.set_password))
    def get_extra(self) -> str:
        """Return encrypted extra-data."""
        if self._extra and self.is_extra_encrypted:
            fernet = get_fernet()
            if not fernet.is_encrypted:
                raise AirflowException(
                    f"Can't decrypt `extra` params for login={self.login}, "
                    f"FERNET_KEY configuration is missing"
                )
            extra_val = fernet.decrypt(bytes(self._extra, "utf-8")).decode()
        else:
            extra_val = self._extra
        if extra_val:
            self._validate_extra(extra_val, self.conn_id)
        return extra_val
    def set_extra(self, value: str):
        """Encrypt extra-data and save in object attribute to object."""
        if value:
            self._validate_extra(value, self.conn_id)
            fernet = get_fernet()
            self._extra = fernet.encrypt(bytes(value, "utf-8")).decode()
            self.is_extra_encrypted = fernet.is_encrypted
        else:
            self._extra = value
            self.is_extra_encrypted = False
    @declared_attr
    def extra(cls):