markdownlint/doc-build/md037.md

This rule is triggered when emphasis markers (bold, italic) are used, but they
have spaces between the markers and the text:

```markdown
Here is some ** bold ** text.

Here is some * italic * text.

Here is some more __ bold __ text.

Here is some more _ italic _ text.
```

To fix this, remove the spaces around the emphasis markers:

```markdown
Here is some **bold** text.

Here is some *italic* text.

Here is some more __bold__ text.

Here is some more _italic_ text.
```

Rationale: Emphasis is only parsed as such when the asterisks/underscores
aren't surrounded by spaces. This rule attempts to detect where
they were surrounded by spaces, but it appears that emphasized text was
intended by the author.