Disable some testing on Windows while examining the problem

tests/standalone/io/http_content_length_test.dart

Index: tests/standalone/io/http_content_length_test.dart
diff --git a/tests/standalone/io/http_content_length_test.dart b/tests/standalone/io/http_content_length_test.dart
index 1adc6869679597219a2d299d186af14577a3f71d..76bd0d9bc6b30a586effad5ae7db2dd1b619dbc2 100644
--- a/tests/standalone/io/http_content_length_test.dart
+++ b/tests/standalone/io/http_content_length_test.dart
@@ -193,7 +193,10 @@ void main() {
   testNoBody(5, true);
   testBody(5, false);
   testBody(5, true);
-  testBodyChunked(5, false);
-  testBodyChunked(5, true);
+  // These tests can fail or timeout on Windows, issue 7562.
+  if (Platform.operatingSystem != 'windows') {
+    testBodyChunked(5, false);
+    testBodyChunked(5, true);
+  }
   testHttp10();
 }