Try to address WPT running OOM

- Continue to reuse the Browser/Env/Isolate, but no start a new session per test.
- Test http server now properly closes the sendFile fd
- Run WPT in ReleaseMode
- Add --quiet option to WPT and some commented out debug code for dumping v8
  memory stats

src/runtime/js.zig

@@ -329,6 +329,27 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
             self.isolate.lowMemoryNotification();
         }
 
+        pub fn dumpMemoryStats(self: *Self) void {
+            const stats = self.isolate.getHeapStatistics();
+            std.debug.print(
+            \\ Total Heap Size: {d}
+            \\ Total Heap Size Executable: {d}
+            \\ Total Physical Size: {d}
+            \\ Total Available Size: {d}
+            \\ Used Heap Size: {d}
+            \\ Heap Size Limit: {d}
+            \\ Malloced Memory: {d}
+            \\ External Memory: {d}
+            \\ Peak Malloced Memory: {d}
+            \\ Number Of Native Contexts: {d}
+            \\ Number Of Detached Contexts: {d}
+            \\ Total Global Handles Size: {d}
+            \\ Used Global Handles Size: {d}
+            \\ Zap Garbage: {any}
+            \\
+            , .{stats.total_heap_size, stats.total_heap_size_executable, stats.total_physical_size, stats.total_available_size, stats.used_heap_size, stats.heap_size_limit, stats.malloced_memory, stats.external_memory, stats.peak_malloced_memory, stats.number_of_native_contexts, stats.number_of_detached_contexts, stats.total_global_handles_size, stats.used_global_handles_size, stats.does_zap_garbage});
+        }
+
         fn promiseRejectCallback(v8_msg: v8.C_PromiseRejectMessage) callconv(.c) void {
             const msg = v8.PromiseRejectMessage.initFromC(v8_msg);
             const isolate = msg.getPromise().toObject().getIsolate();