run_docker_dev.sh fails when the working directory contain spaces

[jackwherry]

Someone in an online community I frequent got a "too many arguments" error from ssh-keygen after running run_docker_dev.sh. After a little investigating, it turned out that a directory in their pwd contained spaces, causing $(pwd) occurrences to become multiple words.

I'm pretty sure that this can be fixed by adding quotes around paths in the script. I'm not too familiar with this codebase, nor do I have a development setup on my current machine, so I didn't make a formal pull request. This issue might also be present in other scripts in this repo. I attached a version of the script that should fix the issue.

It might be a good idea to run these shell scripts through ShellCheck or another linter.

Cheers!