test: [M3-6611] - Add new assertions for linode backup tests

[AzureLatte]

Description 📝

The cypress/e2e/core/linodes/backup-linode.spec.ts have a few shortcomings that should be addressed:

• Navigate to the "Backups" tab of a Linode details page using the UI rather than navigating directly to "/linodes/:id/backups"
• Add test/assertions for canceling Linode backups
• Add test/assertions for error flow when attempting to re-enable Linode backups after canceling (users cannot re-enable backups without first waiting 24 hrs)

Changes 🔄

List any change(s) relevant to the reviewer.

• Add new assertions for linode backup tests

How to test 🧪

yarn cy:run -s "cypress/e2e/core/linodes/backup-linode.spec.ts"

As an Author, I have considered 🤔

• 👀 Doing a self review
• ❔ Our contribution guidelines
• 🤏 Splitting feature into small PRs
• ➕ Adding a changeset
• 🧪 Providing/improving test coverage
• 🔐 Removing all sensitive information from the code and PR description
• 🚩 Using a feature flag to protect the release
• 👣 Providing comprehensive reproduction steps
• 📑 Providing or updating our documentation
• 🕛 Scheduling a pair reviewing session
• 📱 Providing mobile support
• ♿ Providing accessibility support

[github-actions[bot]]

Coverage Report: ✅
Base Coverage: 86.98%
Current Coverage: 86.98%

[linode-gh-bot]

Cloud Manager UI test results

:small_red_triangle: 3 failing tests on test run #2 ↗︎

:x: Failing	:white_check_mark: Passing	:arrow_right_hook: Skipped	:clock1: Duration
3 Failing	450 Passing	2 Skipped	98m 58s

Details

Failing Tests
	Spec	Test
:x:	machine-image-upload.spec.ts	machine image » uploads machine image, mock expired upload event
:x:	linode-storage.spec.ts	linode storage tab » delete disk
:x:	linode-storage.spec.ts	linode storage tab » add a disk

Troubleshooting

Use this command to re-run the failing tests:

yarn cy:run -s "cypress/e2e/core/images/machine-image-upload.spec.ts,cypress/e2e/core/linodes/linode-storage.spec.ts,cypress/e2e/core/linodes/linode-storage.spec.ts"