ENH: Support multiple opening hours intervals for BusinessHour
- [x] closes #15481
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

I'm not sure why, but after rebasing on latest master my previous PR #26400 is automatically closed. So I created a new PR here. I have edited as per all the comments there.