test(SingleInputComponent): add expect and fix warning

[vtsvetkov-splunk]

Issue number:

PR Type

What kind of change does this PR introduce?

• [ ] Feature
• [ ] Bug Fix
• [x] Refactoring (no functional or API changes)
• [ ] Documentation Update
• [ ] Maintenance (dependency updates, CI, etc.)

Summary

Motivation

Every PR has this

but it is just a warning, so it does not fail the build

Changes

• eslint considers this as an error instead of warning
• fix the issue by adding explicit expects

User experience

No change

Checklist

If an item doesn't apply to your changes, leave it unchecked.

• [x] I have performed a self-review of this change according to the development guidelines
• [ ] Tests have been added/modified to cover the changes (testing doc)
• [ ] Changes are documented
• [x] PR title and description follows the contributing principles