chore: Use lib_getopt for all hooks and some style tweaks

[robinbowes]

This change updates terraform_docs and terraform_tfsec to use lib_getopt instead of including the getopt() function as inline code.

I've also tweaked terraform_validate to set more local variables, and set bash strict mode for all these three scripts (set -euo pipefail).

@antonbabenko Please test and confirm the functionality has not changed.

[antonbabenko]

There is something wrong when I run sample code with terraform_docs, terraform_validate, terraform_tfsec hooks.

Example:

$ pre-commit try-repo -a ~/Sites/pre-commit-terraform terraform_docs
===============================================================================
Using config:
===============================================================================
repos:
-   repo: ../../pre-commit-terraform
    rev: 8447a4b0deb03463b79c3efb741589c3c1506d08
    hooks:
    -   id: terraform_docs
===============================================================================
[INFO] Initializing environment for ../../pre-commit-terraform.
Terraform docs...........................................................Failed
- hook id: terraform_docs
- exit code: 2

/var/folders/vy/wm1qhfns0rl564mb6w5w1b3c0000gn/T/tmphnsd74km/repo68xsrh9i/lib_getopt: line 415: space: unbound variable
Try `getopt --help' for more information.

[robinbowes]

Ah, that will be the set -u - let me work on that.

[robinbowes]

@antonbabenko How does this look?

[antonbabenko]

Great! Thanks a lot for this, too.

v1.34.0 has been just released.

[bmonkman]

FYI, this seems to have broken docs parsing for me in a project with multiple sub-modules (Running on MacOS)
Using the version before this, if I parse docs it properly generates docs for all my sub-modules. When I use the version that includes this change it only generates docs for a single module.