Make 'do-not-merge' warning on Renovate PHP PR more visible

[nymous]

Before:

This PR contains the following updates:

Package	Update	Change
php	minor	8.4 → 8.5

Do NOT merge this PR as-is!

This PR is only a reminder that a new PHP version is available, however Renovate doesn't allow us to do everything we need to do.

You need to add the new PHP version to the versions array in update.sh instead of replacing the last.

You also need to update the README.md to list supported versions.

---

After:

This PR contains the following updates:

Package	Update	Change
php	minor	8.4 → 8.5

⚠️ Do NOT merge this PR as-is! ⚠️

This PR is only a reminder that a new PHP version is available, however Renovate doesn't allow us to do everything we need to do.

You need to

• add the new PHP version to the versions array in update.sh instead of replacing the last;

• update the README.md to list supported versions.