Use /bin/sh instead of /bin/bash if possible in scripts

[emanuelb]

There are many scripts in repo that use #!/bin/bash for some of them it's possible to use #!/bin/sh instead without other modifications, for example like in ./eznode/tor/install ./eznode/tor/bin/tor-newnym

it might worth to change it for some other scripts as well if they not relaying to much on bash specific operations (see checkbashisms tool)

[shesek]

As we discussed elsewhere, I don't see a compelling advantage for adapting some of the scripts to use sh, given that the scripts are running in a predictable container environment, don't require portability, and that bash is relied upon heavily and is going to be installed either way.

I'm open to accepting a PR for the scripts that already work with sh as-is and just need their shebang changed, but also okay keeping them with bash for uniformity sake.