Add escape_square_brackets into comment_formats markdown configuration

[lquerel]

The cargo doc command does not properly handle non-escaped text containing square brackets when these brackets are not intended to represent links (e.g., This is a [text] with square brackets that doesn't represent a link). This PR addresses the issue by introducing a new flag escape_square_brackets in the markdown configuration of the comment_formats section.

This new flag ensures that text with square brackets, which are not intended as links, is properly escaped in the generated documentation.

Example:

Input Text:

In some cases, a [URL] may refer to an [IP](http://ip.com) and/or port directly.
The file \[extension\] is extracted \[from] the `url.full`, excluding the leading dot.

Output Without the Flag:

Without the new flag, the following text is returned by the comment filter:

In some cases, a [URL] may refer to an [IP](http://ip.com) and/or port directly.
The file \[extension\] is extracted \[from] the `url.full`, excluding the leading dot.

Output With the Flag Enabled:

When the new flag is enabled, the output becomes:

In some cases, a \[URL\] may refer to an [IP](http://ip.com) and/or port directly.
The file \[extension\] is extracted \[from\] the `url.full`, excluding the leading dot.

Closes #374

[joaopgrassi]

Since we have brackets already in the conventions, what is happening there today? And then, shouldn't this be true by default, as we want to keep the brackets to match the source data? 🤔

[lquerel]

I agree. It’s probably better to have this escaping enabled by default. I will make this change before merging. Thanks