Add shellcheck to pre-commit and make helper scripts clean

[yarikoptic]

What do these changes do?

Fix up found helper shell scripts so they become more robust and shellcheck clean.

Adds shellcheck to pre-commit

Are there changes in behavior for the user?

no

Checklist

• Fix remaining fails

I left following ones not fixed to see if CI would run pre-commit to ensure that nothing sneaks in

❯ pre-commit run --all shellcheck
ShellCheck v0.9.0........................................................Failed
- hook id: shellcheck
- exit code: 1

In tools/build-wheels.sh line 61:
for whl in ${ORIG_WHEEL_DIR}/*/${package_name}-*-linux_${arch}.whl; do
           ^---------------^ SC2231 (info): Quote expansions in this for loop glob to prevent wordsplitting, e.g. "$dir"/*.txt .
                               ^-------------^ SC2231 (info): Quote expansions in this for loop glob to prevent wordsplitting, e.g. "$dir"/*.txt .
                                                       ^-----^ SC2231 (info): Quote expansions in this for loop glob to prevent wordsplitting, e.g. "$dir"/*.txt .


In tools/run_docker.sh line 35:
    docker run --rm -v $(pwd):/io "${manylinux1_image_prefix}${arch}" $dock_ext_args /io/tools/build-wheels.sh "$package_name"
                       ^----^ SC2046 (warning): Quote this to prevent word splitting.

For more information:
  https://www.shellcheck.net/wiki/SC2046 -- Quote this to prevent word splitt...
  https://www.shellcheck.net/wiki/SC2231 -- Quote expansions in this for loop...

[yarikoptic]

hm, it did fail but non-informatively

ShellCheck v0.9.0............................................................Failed
- hook id: shellcheck
- exit code: 1

Executable `docker` not found

apparently that pre-commit action relies on docker :-/

❯ cat pre-commit-hooks.yaml.template
- id: shellcheck
  name: ShellCheck $VERSION
  description: Static analysis tool for shell scripts
  language: docker_image
  entry: $DOCKERHOST/$DOCKERHUB:$VERSION
  types: [shell]
❯ git grep DOCKER
autoupdate:export DOCKERHOST="docker.io"
autoupdate:export DOCKERHUB="koalaman/shellcheck"
autoupdate:  curl "https://registry.hub.docker.com/v2/repositories/$DOCKERHUB/tags" |
pre-commit-hooks.yaml.template:  entry: $DOCKERHOST/$DOCKERHUB:$VERSION

shellcheck seems written in haskell and has linux and OSX builds provided from github releases, but no windows...

anyways -- given above, I just want first to check if you want to keep it or should I drop it and just leave the fixes to scripts? (meanwhile I will push fixup for those remaining issues)