feat(@schematics/angular): generate new projects using TypeScript 3.9

Author: alan-agius4

packages/schematics/angular/utility/latest-versions.ts

@@ -8,7 +8,7 @@
 
 export const latestVersions = {
   // These versions should be kept up to date with latest Angular peer dependencies.
-  Angular: '~10.0.0-next.7',
+  Angular: '~10.0.0-next.8',
   RxJs: '~6.5.4',
   ZoneJs: '~0.10.2',
   TypeScript: '~3.8.3',

packages/schematics/schematics/blank/project-files/package.json.template

@@ -15,7 +15,7 @@
   "dependencies": {
     "@angular-devkit/core": "^<%= coreVersion %>",
     "@angular-devkit/schematics": "^<%= schematicsVersion %>",
-    "typescript": "~3.8.2"
+    "typescript": "~3.9.2"
   },
   "devDependencies": {
     "@types/node": "^12.11.1",