markdownlint/doc-build/md026.md

This rule is triggered on any heading that has one of the specified normal or
full-width punctuation characters as the last character in the line:

```markdown
# This is a heading.
```

To fix this, remove the trailing punctuation:

```markdown
# This is a heading
```

Note: The `punctuation` parameter can be used to specify what characters count
as punctuation at the end of a heading. For example, you can change it to
`".,;:"` to allow headings that end with an exclamation point. `?` is
allowed by default because of how common it is in headings of FAQ-style documents.
Setting the `punctuation` parameter to `""` allows all characters - and is
equivalent to disabling the rule.

Note: The trailing semicolon of
[HTML entity references](https://en.wikipedia.org/wiki/List_of_XML_and_HTML_character_entity_references)
like `©`, `©`, and `©` is ignored by this rule.

Rationale: Headings are not meant to be full sentences. More information:
<https://cirosantilli.com/markdown-style-guide#punctuation-at-the-end-of-headers>