Use Authenticator to 'Update password' -sequence for signedIn user

### Before opening, please confirm:

- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-ui-android/issues?q=is%3Aissue+).

### Which UI component is this feature-request for?

Authenticator

### Please include any relevant guides or documentation you're referencing

https://docs.amplify.aws/android/build-a-backend/auth/manage-users/manage-passwords/#update-password

### Please describe your feature-request in detail.

I know it's possible to use the Amplify Auth library to update the user's password but it would be great if we could use the Authenticator to do it also. One argument for this request is that since password rules are defined in amplifyconfiguration.json and those rules are validated by Authenticator in e.g. SignUp, it would make sense to use Authenticator also for 'Update password' case.

### Initialization steps (if applicable)

_No response_

### Code Snippet

```java
// Put your code below this line.

```

### amplifyconfiguration.json

_No response_

### Additional information and screenshots

_No response_

The request targets the Authenticator component and references Amplify Auth's update-password guide; start by reviewing the existing signed-in Authenticator flow and the password rules in amplifyconfiguration.json. Done means a signed-in user can open an Update password sequence through Authenticator, with the configured rules validated and the password update completed.

Written by the indexing model from the issue text.