Fix some issues in Selenium tests

[SantosGuillamot]

What:

I've made some minor changes to ensure that the Selenium tests pass properly.

Why:

There were some errors in the Proxy and SSR tests in one of the last runs.

How:

I've added a wait in the amp tests and I've upgraded the Edge version to 18.0 because the previous versions were making some specs inconsistent.

Tasks:

• Code

Unrelated Tasks

• TSDocs
• TypeScript
• Unit tests
• End to end tests
• TypeScript tests
• Update starter themes
• Update other packages
• Update community discussions
• Add a changeset (with link to its Feature Discussion if it exists)

Additional Comments

[changeset-bot]

⚠️ No Changeset found

Latest commit: e4cd671

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[github-actions]

ESLint Summary View Full Report

Annotations are provided inline on the Files Changed tab. You can also see all annotations that were generated on the annotations page.

Type	Occurrences	Fixable
Errors	0	0
Warnings	0	0
Ignored	0	N/A

• Result: ✅ success
• Annotations: 0 total

---

^{Report generated by eslint-plus-action}

[codecov]

Codecov Report

Merging #800 (e4cd671) into dev (49ff5ad) will not change coverage.
The diff coverage is n/a.

[github-actions]

ESLint Summary View Full Report

Annotations are provided inline on the Files Changed tab. You can also see all annotations that were generated on the annotations page.

Type	Occurrences	Fixable
Errors	0	0
Warnings	0	0
Ignored	0	N/A

• Result: ✅ success
• Annotations: 0 total

---

^{Report generated by eslint-plus-action}