fix: Undefined index: password in OCA\Files_Sharing\External::Storage

[DeepDiver1975]

Description

How Has This Been Tested?

• test environment:
• test case 1:
• test case 2:
• ...

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Database schema changes (next release will require increase of minor version instead of patch)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Technical debt
• [ ] Tests only (no source changes)

Checklist:

• [ ] Code changes
• [ ] Unit tests added
• [ ] Acceptance tests added
• [ ] Documentation ticket raised:
• [ ] Changelog item, see TEMPLATE

[update-docs[bot]]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.