Upgrade to H2 2.4.240

[snicoll]

Upgrade to H2 2.4.240.

[snicoll]

We can't upgrade to this version as it breaks R2DBC support. There is a PR that needs to be reviewed and a new release to be cut.

[snicoll]

There's unfortunately not much hope we'll get a new r2dbc-h2 release in time so #47658 is our next attempt at unblocking the upgrade.

[snicoll]

Turns out we'll get a release after all. This issue is still blocked until it's out.