Change day of week for dependabot gem updates

[thomasiles]

We want to trial automatic updates for ruby packages.

Currently, we have dependabot gem updates on Sundays, when no one is working.

This commit changes the day of week for dependabot gem updates from Sunday to Tuesday.

The next Tuesday which is a holiday is boxing day 2027.

This change should keep us going until then whilst we refine how the updates are scheduled.

See the dependabot
documentation for more information.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

🎉 A review copy of this PR has been deployed! It is made of up two components

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2. A production copy of forms-admin

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