fix silly next/rules.md modification

It turned out that `next/rules.md` was modified in the section marked
between:

```html
<!-- START: this line starts content from: inc/rules.closed.hdr -->
```

and:

```html
<!-- END: the next line ends content from: inc/rules.closed.hdr -->
```

Instead, `inc/{guidelines,rules}.*.hdr` should be modified as
 `make gen_status` uses these files to form this content.

inc/rules.closed.hdr

@@ -13,9 +13,8 @@ See our
 FAQ on "[rules, guidelines, tools feedback](../faq.html#feedback)"
 as well as our
 FAQ on "[about asking questions](../faq.html#question)"
-about these rules. You might also find the
-FAQ in general useful, especially the
-[FAQ section "How to enter: the bare minimum you need to know"](../faq.html#enter).
+about these rules. You might also find the FAQ in general useful, especially the
+FAQ on "[how to enter the IOCCC](../faq.html#enter)".
 
 Watch both [the IOCCC status page](../status.html) and the
 [@IOCCC mastodon feed](https://fosstodon.org/@ioccc) for information about