[feat]: add gatsby-transformer-pdf

[DSchau]

Summary

Gatsby is all about "bring your own content," and PDF is certainly a means of embedding useful data and content. Let's create a gatsby-transformer-pdf transformer plugin to enable usage of PDF as a content source, and make it queryable with Gatsby's GraphQL layer.

Motivation

• Most common use case will be to make searchable, indexable web sites with Gatsby powered by PDFs as a document store
• To enable this, we'll need to find some way to translate PDF to a usable format, e.g. JSON
  • Haven't used it, but consider pdf2json

Further Detail

Consider looking at existing transformer plugins for inspiration, e.g. gatsby-transformer-json, gatsby-transformer-csv, etc.

[AlexMunoz]

can i work in this issue?

[DSchau]

@AlexMunoz I would love nothing more! Let us know if we can help with anything :)

[LaRuaNa]

@AlexMunoz can i help you with anything to speed up the process? :) Need ASAP this feature :)

[DSchau]

Fixed in #8817 🎉

Thanks so much for the PR @AlexMunoz 💪

Successfully published:
 - gatsby-transformer-pdf@1.0.11
 - gatsby-transformer-yaml@2.1.3

bumped the version due to a little hiccup with our build process!