preamble-re-...-colon

# `preamble-re-...-colon`

The `...` preamble header doesn't contain "standard" or similar words.

## Examples

    error[preamble-re-title-colon]: preamble header `title` should not contain `:`
     --> input.md:4:7
      |
    4 | title: Token Standard: A New Hope
      |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^ prohibited pattern was matched
      |
      = info: the pattern in question: `:`

    error[preamble-re-description-colon]: preamble header `description` should not contain `:`
     --> input.md:4:7
      |
    4 | description: Token Standard: A New Hope
      |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ prohibited pattern was matched
      |
      = info: the pattern in question: `:`

## Explanation

The `preamble-re-...-colon` family of lints prevents the use of colons (`:`) in the `title` and `description` front matter (or preamble) fields.

Support for complex data in the front matter is not perfectly supported in tools.