Fix using password from file

[altafan]

This fixes how the password read from file is used for the auto-unlock feature.

Closes #703.

Please @sekulicd review this.

[what-the-diff[bot]]

PR Summary

• Trim newline and carriage return characters from password Modified the function that reads the password from a file to remove newline (\n) and carriage return characters (\r) to prevent possible issues during authentication.
• Added onUnlock() method call after wallet unlocking This update allows users to unlock their wallet using lncli unlock and then utilize other commands such as lncli listchannels without needing to re-enter their passphrase repeatedly. This improvement simplifies accessing information regarding channels or transactions linked to user account/wallet addresses.