docs: ColumnOption::ForeignKey docs have wrong SQL syntax

https://docs.rs/sqlparser/0.55.0/sqlparser/ast/enum.ColumnOption.html#variant.ForeignKey

says

> A referential integrity constraint (`[FOREIGN KEY REFERENCES () { [ON DELETE ] [ON UPDATE ] | [ON UPDATE ] [ON DELETE ] } []`).

I believe the `FOREIGN KEY (name) REFERENCES` syntax is only for table constraints. That's why it has to say which source columns it talks about!

I believe the syntax for column constraints is just `col_name REFERENCES othertable (othercolumn)`.

As far as I can tell, the sqlparser-rs is already correct. For example, this won't parse:

```sql
-- wrong
CREATE TABLE myschema.mytable (
mycolumn BIGINT NOT NULL,
PRIMARY KEY(mycolumn),
bar BIGINT FOREIGN KEY REFERENCES foo (bar));
```

This does:

```sql
-- good
CREATE TABLE myschema.mytable (
mycolumn BIGINT NOT NULL,
PRIMARY KEY(mycolumn),
bar BIGINT REFERENCES foo (bar));
```

While we're at it, that big syntax literal should live in its own paragraph.

Abre la página enlazada de docs.rs y localiza la documentación de ColumnOption::ForeignKey en el código fuente del repositorio. Verifica la sintaxis de las restricciones de columna con los ejemplos del issue, luego corrige la descripción de la sintaxis y coloca el literal de sintaxis grande en su propio párrafo. La tarea estará terminada cuando la documentación generada describa una sintaxis de columna válida sin el prefijo FOREIGN KEY de la restricción de tabla.

Escrito por el modelo de indexación a partir del texto del issue.