feat: Removed coreutils (realpath) from dependencies for MacOS

[MaxymVlasov]

Put an x into the box if that apply:

• This PR introduces breaking change.
• This PR fixes a bug.
• This PR adds new functionality.
• This PR enhances existing functionality.

Description of your changes

Fixes #336, #349 and #367

How can we test changes

Run any hook on MacOs w/o coreutils

repos:
- repo: https://github.com/antonbabenko/pre-commit-terraform
  rev: 307f48dae422203f31fa888f6cad7d12014ad260
  hooks:

[antonbabenko]

Why did we have a previous solution in the first place? Why there are so many alternative solutions listed here - https://stackoverflow.com/questions/3572030/bash-script-absolute-path-with-os-x ? :)

[yermulnik]

Why there are so many alternative solutions listed here

Coz those who use MacOS are sentenced by Apple to use old, outdated, and EOL'ed NIXish software where Apple doesn't want to conform with licensing in favour of their users suffering from incompetence to install additional modern software using simple solutions like Homebrew and use right tools for the right tasks 🤷🏻
So since there are plenty of such people using pre-commit-terraform I feel like Max is right in replacing the "right tool" with a workaround, which looks most reliable among dozens of alternatives.

[yermulnik]

Let's make happy those people who miss a lot of useful tools.
Linux:

> dpkg -L coreutils | fgrep /bin/ | awk -F/ '{print $NF}' | sort | uniq | wc -l
104

Homebrew on MacOS:

> brew list --verbose coreutils | fgrep /bin/ | awk -F/ '{print $NF}' | sort | uniq | wc -l
133

[MaxymVlasov]

Why did we have a previous solution in the first place?

Because it run out of the box in Linux and realpath was introduced in terraform_validate by mcdonnnj on 4 Apr 2020 (v1.29.0) in 7694fb9

I recheck repo for realpath - now it not exist

[antonbabenko]

This PR is included in version 1.68.0 🎉