fix(gatsby-plugin-mdx): prevent crash when Markdown syntax error

[tureki]

Description

This PR will catch the error from MDX compile. Avoid the develop server crash and show the error message in the browser.

Related Issues

Fixes #16107
Fixes #16502

Before

After

[wardpeet]

Thanks, this seems to work as expected! I'm not sure why we aren't wrapping the whole function in try-catch.

cc @gatsbyjs/themes

[wardpeet]

Thank you fore finding it and fixing it.

@johno approves so, me too! 👍

[gatsbot]

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Thanks again!

[johno]

✨ Thanks! This looks good to me.

Thanks, this seems to work as expected! I'm not sure why we aren't wrapping the whole function in try-catch.

Yeah, good point. I suppose we can roll with this for now and spend some time considering if we want more granular error reporting here in a future PR/issue?