test(@angular/cli): correct unscoped auth E2E test logic

The E2E test for `ng add` with unscoped registry authentication was being incorrectly executed for `pnpm`. The previous logic excluded `npm` and `bun` but erroneously assumed `pnpm` supported this authentication method, which it does not.

This commit refines the `supportsUnscopedAuth` condition to be strictly limited to `yarn`. This ensures the unscoped authentication test case is now accurately targeted, only running against the package manager that supports this behavior, thereby improving the overall reliability of the secure registry tests.

Author: clydin

tests/legacy-cli/e2e/tests/commands/add/secure-registry.ts

@@ -10,15 +10,16 @@ export default async function () {
     // The environment variable has priority over the .npmrc
     delete process.env['NPM_CONFIG_REGISTRY'];
     const packageManager = getActivePackageManager();
-    const supportsUnscopedAuth = packageManager !== 'bun' && packageManager !== 'npm';
+    const supportsUnscopedAuth = packageManager === 'yarn';
     const command = ['add', '@angular/pwa', '--skip-confirmation'];
 
-    await expectFileNotToExist('public/manifest.webmanifest');
-
     // Works with unscoped registry authentication details
     if (supportsUnscopedAuth) {
       // Some package managers such as Bun and NPM do not support unscoped auth.
       await createNpmConfigForAuthentication(false);
+
+      await expectFileNotToExist('public/manifest.webmanifest');
+
       await ng(...command);
       await expectFileToExist('public/manifest.webmanifest');
       await git('clean', '-dxf');
@@ -33,7 +34,7 @@ export default async function () {
     await git('clean', '-dxf');
 
     // Invalid authentication token
-    if (!supportsUnscopedAuth) {
+    if (supportsUnscopedAuth) {
       // Some package managers such as Bun and NPM do not support unscoped auth.
       await createNpmConfigForAuthentication(false, true);
       await expectToFail(() => ng(...command));