gatsby-transformer-rehype with custom plugin not working in Gatsby v3.14

[Kerumen]

I have a custom plugin located in my plugins folder. It's named gatsby-rehype-custom-toc.

The relevant part of my gatsby-config.js looks like this:

{
  resolve: 'gatsby-transformer-rehype',
  options: {
    filter: (node) => node.internal.type === 'GhostPost',
    plugins: [
      { resolve: 'gatsby-rehype-ghost-links' },
      { resolve: 'gatsby-rehype-custom-toc' },
    ],
  },
}

In Gatsby v3.13 everything works fine but when I upgraded to v3.14 it breaks with this error:

"gatsby-transformer-rehype" threw an error while running the createSchemaCustomization lifecycle:

Cannot find module 'gatsby-rehype-custom-toc'

Maybe this is related to this part of the changelog?

[styxlab]

@Kerumen I no longer actively maintain this repo, because I now do everything with Next.js. However, If you want to submit a PR to fix the issue, you are most welcome.