chore: use the same typescript version everywhere (#190)

I was getting warnings from eslint plugins about an unsupported
typescript version (5.8). Then I noticed that the monorepo root is the
only package that doesn't use the "global" version.

---
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under the terms of the Apache-2.0 license

Author: mrgrain

.projen/deps.json

@@ -175,6 +175,7 @@ const repoProject = new yarn.Monorepo({
   repository: 'https://github.com/aws/aws-cdk-cli',
 
   defaultReleaseBranch: 'main',
+  typescriptVersion: TYPESCRIPT_VERSION,
   devDeps: [
     'cdklabs-projen-project-types',
     'glob',