test: unit tests for LocalLoginComponent

[Ma77Ball]

What changes were proposed in this PR?

• Add local-login.component.spec.ts to cover form construction, validators, default-user prefill, and the login/register flows that were previously untested.
• Tests assert that allForms exposes the five expected controls with required, minLength(6), and the custom confirmationValidator, that confirmationValidator returns { confirm: true } on mismatch and {} on match, and that updateConfirmValidator schedules updateValueAndValidity on the confirmation control via setTimeout.
• Tests assert that ngOnInit patches loginUsername/loginPassword only when GuiConfigService.env.defaultLocalUser is populated, that login short-circuits via loginErrorMessage on validation failure and otherwise calls UserService.login with the trimmed username and navigates to queryParams.returnUrl or DASHBOARD_USER_WORKFLOW, and that error paths surface the error's message (or the fallback "Incorrect username or password") through NotificationService.error.
• Tests assert that register enforces password length, password match, and UserService.validateUsername, calls UserService.register with the trimmed username on success and surfaces the account-created notification, and on error notifies with the error's message (or the fallback "Registration failed").

Any related issues, documentation, or discussions?

Closes: #5226

How was this PR tested?

• yarn test --include="src/app/hub/component/about/local-login/local-login.component.spec.ts", 22 tests passing.
• yarn format:fix, 506 files unchanged.

Was this PR authored or co-authored using generative AI tooling?

Co-authored with Claude Opus 4.7 in compliance with ASF