Load app management API schema from branch (#4857)

### WHY are these changes introduced?

Adds support for fetching GraphQL schemas from different branches and loads the App Management API from it's branch.

### WHAT is this pull request doing?

- Adds branch configuration option for schema fetching
- Improves logging during schema fetching to show branch information

### How to test your changes?

Run `dev up` and see how the branched schema is pulled in.

### Measuring impact

- [x] n/a - this doesn't need measurement, e.g. a linting rule or a bug-fix

### Checklist

- [x] I've considered possible cross-platform impacts (Mac, Linux, Windows)
- [x] I've considered possible [documentation](https://shopify.dev) changes

bin/get-graphql-schemas.js

@@ -32,6 +32,7 @@ const schemas = [
     repo: 'shopify',
     pathToFile: 'areas/core/shopify/db/graphql/app_management_schema_unstable_public.graphql',
     localPath: './packages/app/src/cli/api/graphql/app-management/app_management_schema.graphql',
+    branch: 'dd',
   },
   {
     repo: 'shopify',
@@ -79,12 +80,14 @@ function extractPassword(output) {
 async function fetchFileForSchema(schema, octokit) {
   try {
     // Fetch the file content from the repository
+    const branch = schema.branch ?? BRANCH
+    console.log(`\nFetching ${OWNER}/${schema.repo}#${branch}: ${schema.pathToFile} ...`)
     const {data} = await octokit.repos.getContent({
       mediaType: { format: "raw" },
       owner: OWNER,
       repo: schema.repo,
       path: schema.pathToFile,
-      ref: BRANCH,
+      ref: branch,
     })
 
     const content = Buffer.from(data).toString('utf-8')

packages/app/src/cli/api/graphql/app-management/generated/types.d.ts

@@ -71,6 +71,8 @@ export type AppSourceInput = {
 
 /** Possible error codes that can be returned by AppManagement. */
 export type Code =
+  /** Access denied. */
+  | 'ACCESS_DENIED'
   /** An event error. */
   | 'EVENT'
   /** An internal error. */