Use React Query for editor data loading

[bradenmacdonald]

Anytime the editors in src/editors need to load data, or interact with a REST API in any way, they should do so using React Query.

Move the various GET/POST requests out of the Redux state and into React Query apiHooks.ts files, following the same patterns used elsewhere in the Authoring MFE codebase.

A list of all the loaders/mutations is here:

• fetchUnit
• fetchBlock
• fetchStudioView
• createBlock
• saveBlock
• uploadAsset
• allowThumbnailUpload
• uploadThumbnail
• uploadTranscript
• deleteTranscript
• fetchCourseDetails
• fetchImages
• fetchVideos
• uploadVideo
• checkTranscriptsForImport
• importTranscript
• fetchVideoFeatures
• fetchAdvancedSettings