uupdate ci script for windows

.github/workflows/beta.yml

@@ -15,9 +15,8 @@ defaults:
     shell: bash
 
 jobs:
-  # Run the stable test script on the beta channel. Since this branch will soon
-  # be merged into main as our stable-targeting code, this is the key thing we
-  # need to test.
+  # Test all samples on the beta channel. Since the beta channel will soon be
+  # promoted to stable, this branch is only concerned with the beta.
   Beta-CI:
     name: Test flutter beta channel
     runs-on: ${{ matrix.os }}

asset_transformation/grayscale_transformer/bin/grayscale_transformer.dart

@@ -11,8 +11,7 @@ int main(List<String> arguments) {
   // the `--input` option and one for the `--output` option.
   // `--input` is the original asset file that this program should transform.
   // `--output` is where flutter expects the transformation output to be written to.
-  final parser =
-      ArgParser()
+  final parser = ArgParser()
     ..addOption(inputOptionName, mandatory: true, abbr: 'i')
     ..addOption(outputOptionName, mandatory: true, abbr: 'o');
 

tool/ci_script.dart

@@ -15,7 +15,7 @@ Future<void> main() async {
   }
 
   // pub workspace, only run 'get' once
-  await _runCommand('flutter', ['pub', 'get'], workingDirectory: './');
+  await _runCommand('flutter', ['pub', 'get'], workingDirectory: rootDir.path);
 
   final packages = workspace.map((e) => e.toString()).toList();
 
@@ -54,6 +54,7 @@ Future<void> _runCommand(
     executable,
     arguments,
     workingDirectory: workingDirectory,
+    runInShell: true,
     mode: ProcessStartMode.inheritStdio,
   );
   final exitCode = await process.exitCode;