Sharing violation, cannot delete db file

[Aeonic22]

Even if I just make a barebones code like this, without reading or writing any data, it won't delete the db file.
It throws System.IO.IOException : Sharing violation on path ...

SQLiteConnection db = new SQLiteConnection(CwConstants.GetDbPath());
db.Close();
db.Dispose();
GC.Collect();
Thread.Sleep(100);
File.Delete(CwConstants.GetDbPath());

This is within a Play mode Unit test in the Editor.
I've added GC code / sleep just in case, but no effect.
Thanks!