fix(@schematics/update): add pnpm and cnpm as a valid packageManagers

Author: alan-agius4

packages/angular/cli/tasks/install-package.ts

@@ -40,6 +40,7 @@ export function installPackage(
     packageManagerArgs.install,
     packageName,
     packageManagerArgs.silent,
+    packageManagerArgs.noLockfile,
   ];
 
   logger.info(colors.green(`Installing packages for tooling via ${packageManager}.`));
@@ -158,23 +159,20 @@ function getPackageManagerArguments(packageManager: PackageManager): PackageMana
     case PackageManager.Yarn:
       return {
         silent: '--silent',
-        saveDev: '--dev',
         install: 'add',
         prefix: '--modules-folder',
         noLockfile: '--no-lockfile',
       };
     case PackageManager.Pnpm:
       return {
         silent: '--silent',
-        saveDev: '--save-dev',
         install: 'add',
         prefix: '--prefix',
         noLockfile: '--no-lockfile',
       };
     default:
       return {
         silent: '--quiet',
-        saveDev: '--save-dev',
         install: 'install',
         prefix: '--prefix',
         noLockfile: '--no-package-lock',

packages/schematics/update/update/schema.json

@@ -64,7 +64,9 @@
       "default": "npm",
       "enum": [
         "npm",
-        "yarn"
+        "yarn",
+        "cnpm",
+        "pnpm"
       ]
     }
   },