Spinner is misplaced in OData loading message

[matthew-white]

The OData loading message shows text and a spinner. The two are supposed to be next to each other, but right now they aren't:

I noticed this on the entity Data page, but I'm pretty sure it's an issue on the Submissions page as well.

I think the issue is that the following styles have become orphaned and need to be moved into the OdataLoadingMessage component. There are other styles there in addition to the placement of the spinner, e.g., the text color. https://github.com/getodk/central-frontend/blob/b69839d92ef3343d943eaa5ced9888839c5b7d0e/src/components/submission/list.vue#L377-L394