enable lint prefer_final_in_for_each (#47724)

packages/flutter_tools/lib/src/artifacts.dart

diff --git a/packages/flutter_tools/lib/src/artifacts.dart b/packages/flutter_tools/lib/src/artifacts.dart
index 60f6ef6..e9d7c46 100644
--- a/packages/flutter_tools/lib/src/artifacts.dart
+++ b/packages/flutter_tools/lib/src/artifacts.dart
@@ -509,7 +509,7 @@
   String _genSnapshotPath() {
     const List<String> clangDirs = <String>['.', 'clang_x64', 'clang_x86', 'clang_i386'];
     final String genSnapshotName = _artifactToFileName(Artifact.genSnapshot);
-    for (String clangDir in clangDirs) {
+    for (final String clangDir in clangDirs) {
       final String genSnapshotPath = globals.fs.path.join(engineOutPath, clangDir, genSnapshotName);
       if (globals.processManager.canRun(genSnapshotPath)) {
         return genSnapshotPath;