Upgrade to Laravel 11

[williamjallen]

Laravel 11 contains a number of significant improvements to the framework which will be beneficial to future CDash features, but the upgrade path is nontrivial. Laravel changed how column modifications are performed, which will require us to squash all of our existing migrations. Squashing our existing migrations will mean that users will be required to upgrade to the release in which the update occurs before upgrading further. As such, this should be done immediately after the 4.0 major version release.