fix: no direct mutation of nodes (to support Gatsby v4)

[olavea]

Closes #156

[raae]

Instead of the adding cloudinaryAssetData: true to the data defining the Cloudinary asset, the user will have to configure the plugin with the GraphQL types defining the Cloudinary asset. No new nodes will be created for these assets, the image resolvers will be added onto the exiting type.

[raae]

We need help testing this PR, especially on existing larger projects 🙏 It has the same changes as #173, but also adds support for Gatsby v4 🎉 However it still works with Gatsby v3, so test it with your current set up first.

Install the beta version:

• yarn add gatsby-transformer-cloudinary@beta-v4 or npm install gatsby-transformer-cloudinary@beta-v4
• Add the GraphQL type of the data describing an existing Cloudinary asset to the transformTypes plugin options.
  • This would be the GraphQL Type with publicId and cloudName as the minimum. If you add originalWidth, originalHeight and originalFormat you'll save a network request getting that info when querying gatsbyImageData. If its directly on a node it would be the node type.
  • cloudinaryAsset set to true is no longer required, but will do no harm staying present

Test that your gatsby-image components still works in v3:

• Run the project as is and confirm it still works as expected
• Add a ✅ gatsby-image v3 comment below if it does,
• or a ⛔️ gatsby-image v3 with more information if it does not.

Test that your gatsby-image components still works in v4:

• Upgrade to Gatsby v4
• Run the project as is and confirm it still works as expected
• Add a ✅ gatsby-image v4 comment below if it does,
• or a ⛔️ gatsby-image v4 with more information if it does not.

It would also be great if you could test that gatsby-plugin-image works with v4 or v3:

• Install version 1.14.2 to test with Gatsby v3
  • yarn add gatsby-plugin-image@1.14.2or npm install gatsby-plugin-image@1.14.2
• or install version 2.17.0 to test with Gatsby v4
  • yarn add gatsby-plugin-image@2.17.0or npm install gatsby-plugin-image@2.17.0
• Migrate to the new GatsbyImage component and confirm the images you see have not changed
• Add a ✅ gatsby-plugin-image v3 or ✅ gatsby-plugin-image v4 comment below if it does,
• or a ⛔️ gatsby-plugin-image v3 or ⛔️ gatsby-plugin-image v4 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.