Fix hang when separate-process test crashes

pkgs/test/CHANGELOG.md

@@ -4,6 +4,7 @@
 * Change return type on the `body` callback argument to `group` to `void` from
   `dynamic`. This may surface cases where the group callback was erroneously
   returning an ignored value.
+* Fix a hang when a test run with `--compiler exe` crashes.
 
 ## 1.30.0
 

pkgs/test_core/CHANGELOG.md

@@ -4,6 +4,7 @@
 * Change return type on the `body` callback argument to `group` to `void` from
   `dynamic`. This may surface cases where the group callback was erroneously
   returning an ignored value.
+* Fix a hang when a test run with `--compiler exe` crashes.
 
 ## 0.6.16
 

pkgs/test_core/lib/src/runner/vm/platform.dart

@@ -76,6 +76,7 @@ class VMPlatform extends PlatformPlugin {
       outerChannel = MultiChannel<Object?>(jsonSocketStreamChannel(socket));
       cleanupCallbacks
         ..add(serverSocket.close)
+        ..add(socket.close)
         ..add(process.kill);
     } else {
       var receivePort = ReceivePort();