[devicelab] mark uncaught exceptions as flaky (#68906)

* [devicelab] mark uncaight exceptions as flaky

* add print error output

* try and fix test

dev/devicelab/bin/tasks/uncaught_image_error_linux.dart

@@ -26,6 +26,8 @@ Future<void> main() async {
         '-t',
         'lib/main.dart',
         '-d',
+        '--no-pub',
+        '--no-android-gradle-daemon',
         deviceId,
       ];
       final Process process = await startProcess(
@@ -37,6 +39,8 @@ Future<void> main() async {
         .transform(utf8.decoder)
         .transform(const LineSplitter());
 
+      process.stderr.listen(print);
+
       await for (final String line in lines) {
         print(line);
         if (line.contains('ERROR caught by framework')) {

dev/devicelab/manifest.yaml

@@ -84,6 +84,7 @@ tasks:
       completer
     stage: devicelab
     required_agent_capabilities: ["linux/android"]
+    flaky: true
 
   flutter_gallery_android__compile:
     description: >