Moving changesets to dev dependencies

[rowannekabalan]

This dependency has turned up in the dependency tree on Frontend as it's in the dependencies list, however we think this is a dev dependency so we have moved it accordingly.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 5839b01

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

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[domlander]

Changesets is a dev dependency in other Guardian repo's with no issues: https://github.com/search?q=org%3Aguardian+%22%40changesets%2Fcli%22%3A&type=code

[github-actions]

Ad load time test results

For consented, top-above-nav took on average 5558ms to load.
For consentless, top-above-nav took on average 3050ms to load.

Test conditions:

• 5mbps download speed
• 1.5mbps upload speed
• 150ms latency

[emma-imber]

Looks good. Just an FYI that you'll need to add a changeset if you want to release this change, or it'll just be included next time we bump the version - whatever works for you!