`shellcheck` should be able to check all shell script code within `run` blocks

[iynere]

the orb is currently less useful than it could be, at least w.r.t orb development, because most shell scripts in an orb repo exist within the orb source code, in run blocks.

with some smart yaml / string parsing, this orb should be able to do something like :

• find all run blocks that don't have a shell: something key where the something is a non-shell-script-lang
• echo / cat / etc the contents of the run blocks to files
• shellcheck/check all those files

[gmemstr]

Something like https://stackoverflow.com/a/21189044 might come in handy here, but I'm hesitant to recommend it. I think using another common language like Python might need to be a stepping stone here. Otherwise I'm not sure what the best solution is. Looks like this has been done in https://github.com/CircleCI-Public/orb-tools-orb/pull/79, so we could port the work from that to here.

[KyleTryon]

Addressed by Orb pack command by relocating shell scripts outside the yaml file.