add web/ directory to isort checks
- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

pls rebase as this *should* fail (as it doesn''t include the check) and then ping on green @jreback all clear! thanks @el-iot 