📎 Implement `useCharacterClassShortcut` - `unicorn/better-regex`

[Conaclos]

Description

Implement unicorn/better-regex.

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[Conaclos]

I wonder if we should not implement a rule that allows users to choose between character class shortcuts and expanded character classes. Some users may prefer [0-9] instead of \d. The rule could be named useConsistentCharacterClass.

[ematipico]

I'm not very happy about this rule, because it doesn't explain what a "better regex" is. Why is \d is better than [0-9]? Is it a styling decision? Is it a performance?

The documentation is very poor, and it seems that it's not up to our standards.

@Conaclos, if you seek help with this rule, we should provide good information to our contributors regarding documentation.

As per your suggestion, useConsistentCharacterClass seems to be a better name, which means that our rule will behave differently.