feat: support for gatsby-plugin-image

[raae]

We need help testing this PR, especially on existing larger projects 🙏

Install the beta version:

• yarn add gatsby-transformer-cloudinary@beta or npm install gatsby-transformer-cloudinary@beta

Test that gatsby-image still works:

• Run the project as is and confirm it still works as expected
• Add a ✅ gatsby-image comment below if it does,
• or a ⛔️ gatsby-image with more information if it does not.

Test that gatsby-plugin-image works:

• Install version 1.14.2 that works with Gatsby v3
  • yarn add gatsby-plugin-image@1.14.2or npm install gatsby-plugin-image@1.14.2
• Migrate to the new GatsbyImage component and confirm the images you see have not changed
• Add a ✅ gatsby-plugin-image comment below if it does,
• or a ⛔️ gatsby-plugin-image with more information if it does not.

Migration can be done one query at the time, no need to migrate all at once as the fluid and fixed resolvers are still there together with the new gatsbyImageData. Check out the examples for gatsby-image and gatsby-plugin-images side by side.