Update create_integration_test web test to bind to a random port for webdev

Fixes https://github.com/dart-lang/sdk/issues/48489

Change-Id: I551e6fa6eb63e7d3f5652cfa7547fcf7b70976ed
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/234912
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
diff --git a/pkg/dartdev/test/commands/create_integration_test.dart b/pkg/dartdev/test/commands/create_integration_test.dart
index 19f93d8..05d0bf0 100644
--- a/pkg/dartdev/test/commands/create_integration_test.dart
+++ b/pkg/dartdev/test/commands/create_integration_test.dart
@@ -97,7 +97,10 @@
                 p.pubCacheBinPath,
                 Platform.isWindows ? '${command.first}.bat' : command.first,
               ),
-              command.sublist(1),
+              [
+                ...command.sublist(1),
+                'web:0', // Allow for binding to a random available port.
+              ],
               workingDirectory: workingDir,
               environment: {
                 'PUB_CACHE': p.pubCachePath,