* Outlining items for troubleshooting guide for sandboxing.

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: flamber <1447303+flamber@users.noreply.github.com>

* Incorporating minor suggestions

* Incorporating comment from @flamber

* Converting sandboxing troubleshooting guide to prose

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: flamber <1447303+flamber@users.noreply.github.com>

* Johannes' fixes

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Update docs/troubleshooting-guide/sandboxing.md

Co-authored-by: Jeff Bruemmer <jeff@metabase.com>

* Jeff's edits

Co-authored-by: flamber <1447303+flamber@users.noreply.github.com>
Co-authored-by: Jeff Bruemmer <jeff@metabase.com>