introduce examples for different linters to use

[antdking]

feel free to edit this description directly. I'll add them into the description if a comment is added.

Please use this template for flagging them:

**<language>[/<framework>]**
- style: <linter>
- complexity: <linter>
- security: <linter>
- checker: <linter>

In the event of multiple, use sublists:

- checker:
  - <linter>
  - <linter>

ruby:

• style: Rubocop (style, complexity)

python

• style: black

shell

• complexity: shellcheck
• security: shellcheck
• checker: shellcheck