Run tests with latest Ember CLI

Use canary version of ember-cli on master branch, until we ge get a stable/beta release on npm, which includes better support of `--typescript` ([PR](ember-cli/ember-cli#10283)). Cleans up previous weirdness.

.github/workflows/ci.yml

@@ -43,18 +43,22 @@ jobs:
         # waiting on a an api from vitest for querying
         # the list of tests ahead of time before running them.
         #
-        # It would be great if vitest had a flag to give us the JSON of all the tests, 
-        # so we could be sure we don't miss anything 
+        # It would be great if vitest had a flag to give us the JSON of all the tests,
+        # so we could be sure we don't miss anything
         # and then generate this list from a previous C.I. job
         slow-test:
           - defaults with npm
           - defaults with yarn
           - defaults with pnpm
 
+          # TypeScript
+          - typescript with npm
+          - typescript with yarn
+          - typescript with pnpm
+
           # flags
           - addon-location
           - test-app-location
-          - typescript
           - addon-only
 
           # existing monorepo

index.js

@@ -176,12 +176,17 @@ module.exports = {
 
     if (options.typescript) {
       const needsVersion = '4.9.0-beta.0';
+      const recommendedVersion = '5.2.0-beta.0';
       const hasVersion = this.project.emberCLIVersion();
 
       if (lt(hasVersion, needsVersion)) {
         this.ui.writeWarnLine(
           `Your version ${hasVersion} of Ember CLI does not support the --typescript flag yet. Please run \`ember install ember-cli-typescript\` in the ${testAppInfo.location} folder manually!`
         );
+      } else if (lt(hasVersion, recommendedVersion)) {
+        this.ui.writeWarnLine(
+          `We recommend using Ember CLI >= ${recommendedVersion} for the best blueprint support when using TypeScript!`
+        );
       }
     }
   },