I'm still puzzled by "bring the bike inside". Is this your bike? Was it just sitting in your garage? If so, it shouldn't be necessary to clean it. I'd give it a cleaning if it were someone else's bike but not my ownonly used by me. The virus only survives for 3 days or so max, and that trainer has been in the box longer than that. The outside delivery box may have been touched and that may require a wipe down, or just leave it somewhere for a few days itself. I can tell you that an hour on a trainer will feel like 3 days anyway...
But soap and water is the best if you must. I use it on my bike all the time anyway. I have a whole setup for bike washing that I use every month or so, depending on use.