Change order of code block formatting to prevent removal of backticks

[mtandre]

Description of Change

This adjusts the order of the triple backtick code block formatting so that backticks (`) in the code are preserved.

The formatCodeContent() function replaces backticks with their html entities and then the conversion to text via cheerio.text() reverts them back into backticks. So then, when the single backtick formatter runs it replaces those backticks within the triple backtick code blocks and the disappear from the rendered code block. This prevents that by moving the formatCodeContent() to after the cheerio.text() conversion.

This also add a backtick example into the triple backtick code block in the supportedFormats.html fixture for testing.

Related Issue

Fixes #294

Motivation and Context

I recently ran into this issue where backtick in code blocks were disappearing and noticed there was open issue for it.

Checklist

• Ran npm run lint and updated code style accordingly
• npm run test passes
• PR has a description and all contributors/stakeholder are noted/cc'ed
• tests are updated and/or added to cover new code
• relevant documentation is changed and/or added

[afischer]

Hey @mtandre, thanks for the contribution (and added test!)

Still seeing slightly weird behavior:

• Inline code seems to still incorrectly escape backticks
• Block code with a language is great!
• Block code without a language eats the first line (NB: I just tested this on main and it is still an issue, so this is a different bug. Feel free to fix if you can in this PR, otherwise I we can follow up

Here's the text I used to generate this:

Inline code `const js = `one ${true} language`;`


Block code with language:


```js
const js = `one ${true} language`
console.log(js)
```
Block code without language:
```
const js = `one ${true} language`
console.log(js)
```

[mtandre]

@afischer I've updated the PR:

• support the backticks in inline code blocks by using double backticks, similar to markdown
• fix the bug that eats first line of a code block when no language hint exists by updating the regex and moving the removal of the language hint to after it is confirmed as a language

Let me know your thoughts.

[afischer]

This looks great! I'll add examples of all these to our supported documents file.