`LocalCalendarStoreTest.testUpdateAccount_updatesOwnerAccount` sometimes fails

[rfc2822]

at.bitfire.davdroid.resource.LocalCalendarStoreTest > testUpdateAccount_updatesOwnerAccount[virtual] FAILED 
	android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0
	at android.database.AbstractCursor.checkPosition(AbstractCursor.java:521)

See https://github.com/bitfireAT/davx5-ose/actions/runs/19539162889/job/55940590979?pr=1825

[devvv4ever]

https://github.com/bitfireAT/davx5/actions/runs/19542678245/job/55953060227

[rfc2822]

https://github.com/bitfireAT/davx5/actions/runs/19634493261/job/56221823258

[rfc2822]

Reopening. Guess we must use Assume too (which again makes the test relatively useless) …

https://github.com/bitfireAT/davx5-ose/actions/runs/20095525389/job/57652858829?pr=1867