Update backpressuring-in-streams.md

Signed-off-by: Claudio W <[email protected]>

pages/zh-cn/docs/guides/backpressuring-in-streams.md

@@ -215,26 +215,27 @@ sys          8.79
 
 .write()`方法的<a href="https://github.com/nodejs/node/blob/55c42bc6e5602e5a47fb774009cfe9289cb88e71/lib/_stream_writable.js#L239" fo="25">返回值</a>，我们得到以下结果：</p>
 
-# <pre><code>Without respecting the return value of .write():
-
-real 54.48
-user 53.15
-sys 7.43
-1524965376 maximum resident set size
-0 average shared memory size
-0 average unshared data size
-0 average unshared stack size
-373617 page reclaims
-3139 page faults
-0 swaps
-18 block input operations
-199 block output operations
-0 messages sent
-0 messages received
-1 signals received
-25 voluntary context switches
-629566 involuntary context switches
-`</pre>
+```
+    Without respecting the return value of .write():
+    ==================================================
+    real        54.48
+    user        53.15
+    sys          7.43
+    1524965376  maximum resident set size
+             0  average shared memory size
+             0  average unshared data size
+             0  average unshared stack size
+        373617  page reclaims
+          3139  page faults
+             0  swaps
+            18  block input operations
+           199  block output operations
+             0  messages sent
+             0  messages received
+             1  signals received
+            25  voluntary context switches
+        629566  involuntary context switches
+```
 
 虚拟内存占用的最大的字节块达到了 1.52 gb。