Running with readOnlyRootFilesystem

Hi,

support for Read only root fs would be great. So far I've encountered two issues:

Mysql container init wants to use `/tmp` and `/var/run/mysqld`, emptyDir (or an option to add emptyDir) volume would fix that easily (tested it).

Lake really wants to log to `/app/logs/`, same thing, emptyDir fixes it easily.

UI wants to create `/etc/nginx/conf.d/default.conf`. If I'm reading the [source](https://github.com/apache/incubator-devlake/blob/main/config-ui/nginx.sh) right, this might be a bit trickier to accomplish, the solution that comes to mind is a different entrypoint and skipping the templating, using a configmap instead? But maybe there's something more simple.

edit: Lake also wants `/tmp` during runtime