Added in formatting guidance for links that appear in rules.
## Review
A dedicated reviewer checked the rule description successfully for:
- [x] logical errors and incorrect information
- [x] information gaps and missing content
- [x] text style and tone
- [x] PR summary and labels follow [the
guidelines](https://github.com/SonarSource/rspec/#to-modify-an-existing-rule)
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Co-authored-by: Martin Strecker <103252490+martin-strecker-sonarsource@users.noreply.github.com>
55e9cb9961